JP7227858B2 - Seismic isolation device - Google Patents

Description

The present invention relates to a seismic isolation device.

A conventional seismic isolation device includes a laminated structure having hard material layers and soft material layers alternately laminated in the vertical direction, and the hard material layers are provided on the upper and/or lower end sides of the laminated structure. , which has a larger diameter than other hard material layers arranged axially inward with respect to the hard material layer (for example, Patent Document 1). According to Patent Document 1, with such a configuration, when the seismic isolation device is deformed in the horizontal direction, stress concentration in the vicinity of the flange plate in the laminated structure can be suppressed, and the risk of buckling can be reduced. ing.

JP 2014-47926 A

However, in the above-described seismic isolation device, when the seismic isolation device is deformed in the horizontal direction, in the laminated structure, the outer peripheral side portion of the large-diameter hard material layer and the axially outer side (flange plate side) portion thereof However, there is a risk of warping inward in the axial direction away from the flange plate (hereinafter, also referred to as "turning up").

SUMMARY OF THE INVENTION An object of the present invention is to provide a seismic isolation device capable of suppressing lifting.

A seismic isolation device of the present invention is a seismic isolation device provided with a laminated structure having hard material layers and soft material layers alternately laminated in the vertical direction,
The laminated structure has a small-diameter hard material layer, which is the hard material layer, and is adjacent to the small-diameter hard material layer on at least one of its upper and lower ends in the axial direction outside. a large-diameter hard material layer that is the hard material layer having a larger diameter than the small-diameter hard material layer,
The large-diameter hard material layer is characterized by having higher flexural rigidity than the small-diameter hard material layer or the hard material layer having a smaller diameter than the large-diameter hard material layer.
According to the seismic isolation device of the present invention, it is possible to suppress curling up.

In the seismic isolation device of the present invention, it is preferable that the large-diameter hard material layer has a greater axial thickness than the small-diameter hard-material layer or the hard-material layer having a smaller diameter than the large-diameter hard-material layer.
This makes it possible to easily adjust the flexural rigidity of the large-diameter hard material layer.

In the seismic isolation device of the present invention, the material constituting the large-diameter hard material layer is the material constituting the small-diameter hard material layer, or the material constituting the hard material layer having a diameter smaller than that of the large-diameter hard material layer. Young's modulus is preferably larger than
This makes it possible to easily adjust the flexural rigidity of the large-diameter hard material layer.

In the seismic isolation device of the present invention, the laminated structure has a plurality of pairs of the small-diameter hard material layer and the large-diameter hard material layer on at least one of the upper side and the lower side thereof. and
Among the plurality of large-diameter hard material layers included in the plurality of pairs, at least a step in the large-diameter hard material layer located on the outer peripheral side of the small-diameter hard material layer paired with the large-diameter hard material layer The large-diameter hard material layer having the maximum radial length of the portion is the small-diameter hard material layer paired with the large-diameter hard material layer, or the hard material having a smaller diameter than the large-diameter hard material layer. It is preferable that the flexural rigidity is higher than that of the layer.
As a result, it is possible to further suppress curling up.

In the seismic isolation device of the present invention, the laminated structure has a plurality of pairs of the small-diameter hard material layer and the large-diameter hard material layer on at least one of the upper side and the lower side thereof. Preferably, each of the large-diameter hard material layers of at least two pairs among the plurality of pairs has higher bending rigidity than the small-diameter hard material layer paired with the large-diameter hard material layer.
As a result, it is possible to further suppress curling up.

In the seismic isolation device of the present invention, the plurality of large-diameter hard material layers included in the at least two pairs are larger than the small-diameter hard-material layers paired with the large-diameter hard-material layers in the large-diameter hard-material layers. It is preferable that the larger the radial length of the step portion located on the outer peripheral side, the higher the bending rigidity.
As a result, it is possible to further suppress curling up.

ADVANTAGE OF THE INVENTION According to this invention, the seismic isolation apparatus which can suppress a turn-up can be provided.

1 is an axial cross-sectional view of a seismic isolation device according to a first embodiment of the present invention; FIG. FIG. 7 is an axial cross-sectional view of a seismic isolation device according to a second embodiment of the present invention; FIG. 7 is an axial cross-sectional view of a seismic isolation device according to a third embodiment of the present invention; FIG. 11 is an axial cross-sectional view showing part of a seismic isolation device according to a fourth embodiment of the present invention; FIG. 11 is an axial cross-sectional view showing part of a seismic isolation device according to a fifth embodiment of the present invention; FIG. 11 is an axial cross-sectional view showing part of a seismic isolation device according to a sixth embodiment of the present invention;

The seismic isolation device of the present invention is designed to suppress the transmission of earthquake vibrations to structures (for example, buildings such as buildings, condominiums, detached houses, warehouses, bridges, etc.). It is preferred when placed between structures.
An embodiment of a seismic isolation device according to the present invention will be exemplified below with reference to the drawings. The same reference numerals are given to common components in each figure.

FIG. 1 is a drawing for explaining a seismic isolation device 1 according to a first embodiment of the present invention. FIG. 1 is an axial cross-sectional view of a seismic isolation device 1 according to this embodiment.

As shown in FIG. 1, the seismic isolation device 1 of this embodiment includes a pair of upper and lower flange plates 21 and 22 (hereinafter also referred to as "upper flange plate 21" and "lower flange plate 22", respectively), and a laminated plate. a structure 3;

In this specification, the “central axis O” of the seismic isolation device 1 (hereinafter also simply referred to as the “central axis O”) is the central axis of the laminated structure 3 . A central axis O of the seismic isolation device 1 is oriented so as to extend in the vertical direction. In this specification, the “axial direction” of the seismic isolation device 1 is a direction parallel to the central axis O of the seismic isolation device 1 . The “axial direction inner side” of the seismic isolation device 1 refers to the side close to the axial direction center of the laminated structure 3, and the “axial direction outer side” of the seismic isolation device 1 refers to the axial direction center of the laminated structure 3. , the side farther from (the side closer to the flange plates 21, 22). Further, the “perpendicular direction” of the seismic isolation device 1 is a direction perpendicular to the axial direction of the seismic isolation device 1 . In addition, the terms "inner peripheral side", "outer peripheral side", "radial direction", and "circumferential direction" of the seismic isolation device 1 refer to "inner peripheral side", They refer to "peripheral side", "radial direction", and "circumferential direction" respectively. "Upper" and "lower" refer to "upper" and "lower" in the vertical direction, respectively.

The upper flange plate 21 has a structure (for example, buildings such as buildings, condominiums, detached houses, and warehouses, and bridges, etc.) superstructures (building bodies, etc.) placed on the upper flange plate 21. It is configured to be connected to the superstructure. The lower flange plate 22 is arranged below the upper flange plate 21 and configured to be connected to the lower structure (foundation, etc.) of the structure. The upper flange plate 21 and the lower flange plate 22 are preferably constructed of metal, more preferably steel. In this embodiment, the upper flange plate 21 and the lower flange plate 22 have a circular outer edge shape in cross section perpendicular to the axis (not shown). However, the upper flange plate 21 and the lower flange plate 22 may have any outer edge shape such as a polygonal shape (such as a square shape) in the axial cross section.

The laminated structure 3 is arranged between the upper flange plate 21 and the lower flange plate 22 . The laminated structure 3 has a plurality of hard material layers 4 , a plurality of soft material layers 5 and a covering layer 6 . The hard material layers 4 and the soft material layers 5 are alternately laminated in the vertical direction. Each hard material layer 4 and each soft material layer 5 are arranged coaxially. Located on O. Soft material layers 5 are arranged at both upper and lower ends of the laminated structure 3 . A pair of soft material layers 5 arranged at both upper and lower ends of the laminated structure 3 are fixed to the upper flange plate 21 and the lower flange plate 22, respectively.

The hard material layer 4 is made of a hard material. As the hard material forming the hard material layer 4, metal is preferable, and steel is more preferable.
The soft material layer 5 is made of a soft material having lower rigidity than the hard material layer 4 . As the soft material forming the soft material layer 5, an elastic body is preferable, and rubber is more preferable. As the rubber constituting the soft material layer 5, natural rubber or synthetic rubber (such as high damping rubber) is suitable.

The coating layer 6 covers the outer surfaces of the hard material layer 4 and the soft material layer 5 . The material forming the coating layer 6 is preferably an elastic body, more preferably rubber. The material forming the coating layer 6 may be the same as the soft material forming the soft material layer 5 or may be different from the soft material forming the soft material layer 5 .
The covering layer 6 is configured integrally with the soft material layer 5 .
In the present embodiment, the coating layer 6 covers the entire outer surface of the hard material layer 4 and the soft material layer 5 , and thus constitutes the entire outer surface of the laminated structure 3 . . However, the coating layer 6 may cover only a part of the outer peripheral surface of the hard material layer 4 and the soft material layer 5, and thus constitute only a part of the outer peripheral surface of the laminated structure 3. may be In addition, the coating layer 6 may not be provided, in which case the outer peripheral surface of the laminated structure 3 is composed only of the outer peripheral surfaces of the hard material layer 4 and the soft material layer 5 .

In this embodiment, the hard material layer 4, the soft material layer 5, and the coating layer 6 each have a circular outer edge shape in the cross section perpendicular to the axis. However, the hard material layer 4, the soft material layer 5, and the coating layer 6 may each have any non-circular outer edge shape such as a polygonal shape (such as a square) in the cross section perpendicular to the axis.
In this specification, the "outer diameter" of each of the laminated structure 3, the hard material layer 4, the soft material layer 5, and the coating layer 6 means that they have a non-circular outer edge shape in a cross section perpendicular to the axis. If so, it refers to the diameter of these circumscribed circles in the axial section.

As shown in FIG. 1, in this embodiment, the laminated structure 3 has a hard material layer 4 on at least one of its upper and lower sides (both in the example of FIG. 1). The small-diameter hard material layer 4S and the large-diameter hard material that is the hard material layer 4 that is adjacent to the small-diameter hard material layer 4S on the outer side in the axial direction and has a larger diameter (i.e., a larger outer diameter) than the small-diameter hard material layer 4S. layer 4L; In the example of FIG. 1, the laminated structure 3 has pairs of one small-diameter hard material layer 4S and one large-diameter hard material layer 4L adjacent to each other on both upper and lower end sides. Each has 4P.
One pair 4P consists of one small-diameter hard material layer 4S and one large-diameter hard material layer 4L adjacent to each other. The hard material layers 4 do not constitute the pair 4P (that is, when focusing on the one pair 4P, each hard material layer 4 other than the small-diameter hard-material layer 4S and the large-diameter hard-material layer 4L is, for example, Even if they have the same diameter as the small-diameter hard material layer 4S or the large-diameter hard material layer 4L, they are not called the small-diameter hard material layer 4S or the large-diameter hard material layer 4L).
In the present embodiment, the small-diameter hard material layer 4S is located axially outside the center of the laminated structure 3 in the axial direction. The hard material layers 41 located axially inward of the small-diameter hard material layers 4S each have the same diameter (that is, the same outer diameter) as the small-diameter hard material layers 4S. In addition, in this embodiment, the laminated structure 3 has two hard material layers 42 positioned axially outside the large-diameter hard material layer 4L. The hard material layer 42 has the same diameter (that is, the same outer diameter) as the large-diameter hard material layer 4L. However, the large-diameter hard material layer 4</b>L may be positioned most outward in the axial direction among the plurality of hard material layers 4 forming the laminated structure 3 .
In this specification, a portion 4LM of the large-diameter hard material layer 4L, which is located on the outer peripheral side of the small-diameter hard material layer 4S, is referred to as a "stepped portion (4LM)."

In the example of FIG. 1, the large-diameter hard material layer 4L is larger than the small-diameter hard material layer 4S, or the small-diameter hard material layer 4S and the hard material layer 41, which are hard material layers smaller in diameter than the large-diameter hard material layer 4L. , with high bending stiffness. More specifically, in FIG. 1, the large-diameter hard material layer 4L has higher flexural rigidity than the small-diameter hard material layer 4S or the hard material layer smaller than the large-diameter hard material layer 4L. Here, "a hard material layer having a smaller diameter than the large-diameter hard material layer 4L" refers to all hard material layers having a smaller diameter than the large-diameter hard material layer 4L, and thus includes the small-diameter hard material layer 4S. That is, in the example of FIG. 1, the large-diameter hard material layer 4L is the small-diameter hard-material layer 4S, or the small-diameter hard-material layer 4S and the hard-material layer 41, which are hard-material layers smaller in diameter than the large-diameter hard-material layer 4L. Bending stiffness is higher than More specifically, in the example of FIG. 1, the large-diameter hard material layer 4L has higher bending rigidity than the small-diameter hard material layer 4S, and the large-diameter hard material layer 4L has a smaller diameter than the large-diameter hard material layer 4L. The bending rigidity is higher than that of the small-diameter hard material layer 4S and any of the hard material layers 41 (in this example, all of them are located axially inside the small-diameter hard material layer 4S).
The large-diameter hard material layer 4L may have higher bending rigidity than the small-diameter hard material layer 4S alone. However, as shown in the example of FIG. 1 described above, the large-diameter hard material layer 4L is larger than all hard material layers (the small-diameter hard material layer 4S and the hard material layer 41) smaller in diameter than the large-diameter hard material layer 4L. , preferably have high bending stiffness.

The effects of the seismic isolation device 1 of this embodiment will be described below.
First, in the seismic isolation device 1 of the present embodiment, as described above, the laminated structure 3 has a hard material on at least one of its upper and lower sides (both in the example of FIG. 1). a small-diameter hard material layer 4S that is the layer 4, and a large-diameter hard material layer 4L that is the hard material layer 4 that is adjacent to the small-diameter hard material layer 4S on the outer side in the axial direction and has a larger diameter than the small-diameter hard material layer 4S, have. As a result, compared to the case where all the hard material layers 4 of the laminated structure 3 have the same diameter as the small-diameter hard material layer 4S, the hard material layers 4 are arranged in the axial direction when the seismic isolation device 1 is horizontally deformed. In addition, since the laminated structure 3 is supported more firmly in the axial direction, the seismic isolation device 1 is less likely to buckle (in other words, the buckling resistance of the seismic isolation device 1 can be improved. ). Moreover, compared with the case where all the hard material layers 4 of the laminated structure 3 have the same diameter as the large-diameter hard material layer 4L, the seismic isolation performance of the seismic isolation device 1 can be improved.

Furthermore, in the present embodiment, the large-diameter hard material layer 4L is the small-diameter hard material layer 4S adjacent to the inner side in the axial direction, or a hard material layer smaller in diameter than the large-diameter hard material layer 4L (in this example, the small-diameter hard material layer 4S). It has a higher bending stiffness than the layer 4S and the hard material layer 41). As a result, when the seismic isolation device 1 is deformed in the horizontal direction, a repulsion directed inward in the axial direction acts on the stepped portion 4LM of the large-diameter hard material layer 4L of the laminated structure 3 and portions axially outward therefrom. The force can be resisted, and the stepped portion 4LM of the large-diameter hard material layer 4L and the axially outer portion thereof can be prevented from curling up inward in the axial direction. Therefore, it is possible to reduce the possibility that the soft material layer 5 is fatigued or damaged in the stepped portion 4LM and the axially outer portion thereof, and thus the durability of the seismic isolation device 1 can be improved.

Means for adjusting the bending rigidity of the large-diameter hard material layer 4L are not particularly limited. To easily adjust the flexural rigidity of the large-diameter hard material layer 4L by making the thickness in the axial direction larger than that of the small-diameter hard material layer (in this example, the small-diameter hard material layer 4S and the hard material layer 41). can be done.

In this embodiment, when the axial thickness of the large-diameter hard material layer 4L is referred to as thickness t1, the axial thickness of the small-diameter hard material layer 4S is referred to as thickness t2, and the axial thickness of hard material layer 41 is referred to as thickness t3, the thickness t1/t2 is preferably 150 to 500%, and thickness t1/t3 is preferably 150 to 500%.
Note that the thicknesses t2 and t3 may be the same or different, but from the viewpoint of manufacturability, they are preferably the same as in this example.

As means for adjusting the bending rigidity of the large-diameter hard material layer 4L, instead of the means for increasing the axial thickness of the large-diameter hard material layer 4L, or together with the means for increasing the axial thickness, a large-diameter hard material layer 4L may be used. The material constituting the material layer 4L is the material constituting the small-diameter hard material layer 4S, or the material constituting the hard material layer (the small-diameter hard material layer 4S and the hard material layer 41) having a smaller diameter than the large-diameter hard material layer 4L. The flexural rigidity of the large-diameter hard material layer 4L can also be easily adjusted by setting the Young's modulus to be larger than that. Here, Young's modulus is measured according to JISZ2241.

For example, the material forming the small-diameter hard material layer 4S and the hard material layer 41 is stainless steel, and the material forming the large-diameter hard material layer 4L is the material forming the small-diameter hard material layer 4S and the hard material layer 41. Stainless steel having a higher Young's modulus, rolled steel, or the like can be used.

From the viewpoint of improving the effect of preventing curling, the Young's modulus ratio of E1/E2 is 1.2 or more, where E1 is the Young's modulus of the large-diameter hard material layer 4L and E2 is the Young's modulus of the small-diameter hard material layer 4S. is preferred, and 1.5 or more is more preferred.

In addition, in each embodiment described in this specification, as in the example shown in FIG. Advantageously, a pair 4P consisting of layers 4L is provided. In this case, the anti-buckling performance of the seismic isolation device 1 can be improved as compared with the case where the pairs 4P are provided only at one of the upper and lower ends of the laminated structure 3 .

However, as in the second embodiment shown in FIG. 2, even if the pair 4P consisting of the small-diameter hard material layer 4S and the large-diameter hard material layer 4L is provided only on the lower end side of the laminated structure 3 Alternatively, as in the third embodiment shown in FIG. 3, a pair 4P consisting of a small-diameter hard material layer 4S and a large-diameter hard material layer 4L is provided only on the upper end side of the laminated structure 3. may In these cases, compared to the case where the pairs 4P are provided on both the upper and lower end sides of the laminated structure 3 (FIG. 1), the laminated structure 3 Since it becomes easy to perform lamination work of each hard material layer 4 and each soft material layer 5 that constitute the , the productivity of the seismic isolation device 1 can be improved. In these cases, the hard material layers 4 have the same diameter at the end of the laminated structure 3 where the pair 4P is not provided, and the stepped portion 4LM does not exist. As a result, there is no possibility of the sheet being turned up when it is deformed in the horizontal direction. Therefore, the large-diameter hard-material layer 4L is replaced with the small-diameter hard-material layer 4S or the large-diameter hard-material layer only on the upper and lower ends of the laminated structure 3 where the pair 4P is provided. If the flexural rigidity is higher than that of the hard material layer (the small-diameter hard material layer 4S and the hard material layer 41) with a diameter smaller than 4L, it is sufficient from the viewpoint of suppressing the turning-up.

In each embodiment of this specification, at least one of its upper side and lower side (FIGS. In the example shown in FIG. 6, a plurality of (three in the examples shown in FIGS. 4 to 6) pairs 4P each composed of a small-diameter hard material layer 4S and a large-diameter hard material layer 4L are formed on at least the lower end portion side. may have.

In the laminated structure 3 shown in FIG. 4, the radial lengths L1, L2 and L3 of the step portions 4LM1, 4LM2 and 4LM3 of each pair 4P are different from each other. More specifically, the radial lengths L1, L2, and L3 of the stepped portions 4LM1, 4LM2, and 4LM3 of each pair 4P are longer (i.e., the length L1 <L2<L3).
Here, if each of the hard material layers 4 has the same bending rigidity, the longer the radial length of the stepped portion 4LM, the more the stepped portion of the laminated structure 3 becomes larger when the seismic isolation device 1 is deformed in the horizontal direction. The portion 4LM and portions axially outward therefrom tend to warp axially inward (turning up). From this point of view, when the laminated structure 3 has a plurality of pairs 4P consisting of the small-diameter hard material layer 4S and the large-diameter hard material layer 4L on at least one end side of the upper side and the lower side. , as shown in FIG. 4, at least a large-diameter hard material layer 4L having a stepped portion 4LM having the maximum radial length (in this example, a large-diameter hard material layer 4L having a stepped portion 4LM3 having a length L3 in the radial direction). The diameter hard material layer 4L3) is a small diameter hard material layer 4S (in this example, a small diameter hard material layer 4S3) paired with the large diameter hard material layer 4L, or a hard material having a smaller diameter than the large diameter hard material layer 4L. Bending rigidity is higher than the layers (in this example, the small diameter hard material layer 4S3, the large diameter hard material layer 4L2, the small diameter hard material layer 4S2, the large diameter hard material layer 4L1, the small diameter hard material layer 4S1, and the hard material layer 41). is preferred. As a result, it is possible to further suppress curling up.
In the example of FIG. 4, bending rigidity is enhanced by increasing the thickness of the large-diameter hard material layer 4L.

In the laminated structure 3 shown in FIG. 5, the radial lengths L1, L2 and L3 of the step portions 4LM1, 4LM2 and 4LM3 of each pair 4P are the same.
In the present embodiment, when the laminated structure 3 has a plurality of pairs 4P consisting of the small-diameter hard material layer 4S and the large-diameter hard material layer 4L on at least one end side of its upper and lower sides, Each large-diameter hard material layer 4L of at least two (more preferably all) pairs 4P out of the plurality of pairs 4P has bending rigidity higher than that of the small-diameter hard material layer 4S paired with the large-diameter hard material layer 4L. High is preferred. More specifically, in FIG. 5, the large-diameter hard material layer 4L2 has higher bending rigidity than the small-diameter hard material layer 4S2, and the large-diameter hard material layer 4L3 has higher bending rigidity than the small-diameter hard material layer 4S3. As a result, it is possible to further suppress curling up.
In this example, although the large-diameter hard material layers 4L2 and 4L3 have the same flexural rigidity, they may have different flexural rigidity.

Note that the laminated structure 3 in this embodiment is not limited to the example shown in FIG. It is sufficient if the bending rigidity is higher than that of the material layer 4S. More preferably, in at least two pairs including the axially outermost pair 4P3, the large-diameter hard material layer 4L preferably has a higher flexural rigidity than the small-diameter hard material layer 4S.

In the laminated structure 3 shown in FIG. 6, the radial lengths L1, L2 and L3 of the step portions 4LM1, 4LM2 and 4LM3 of each pair 4P are different from each other. More specifically, similarly to the laminated structure 3 shown in FIG. 4, the radial lengths L1, L2, and L3 of the stepped portions 4LM1, 4LM2, and 4LM3 of each pair 4P are arranged more outward in the axial direction. Long radial length (ie, length L1<L2<L3).
In the seismic isolation device 1, if the large-diameter hard material layer 4L has the stepped portion 4LM located on the outer peripheral side of the small-diameter hard material layer 4S, a force that warps inward in the axial direction tends to act on the stepped portion 4LM. . Furthermore, as described above, if the hard material layers 4 each have the same bending rigidity, the longer the radial length of the stepped portion 4LM, the more , the stepped portion 4LM and the axially outer portion thereof are likely to warp (turn up) inwardly in the axial direction. From this point of view, in the present embodiment, the laminated structure 3 has a plurality of pairs 4P formed of the small-diameter hard material layer 4S and the large-diameter hard material layer 4L on at least one end side of the upper side and the lower side. At least two pairs of the large-diameter hard material layers 4L among the plurality of pairs 4P have higher bending rigidity than the small-diameter hard material layers 4S paired with the large-diameter hard material layers 4L. 6, the plurality of large-diameter hard material layers 4L (large-diameter hard material layers 4L1, 4L2, and 4L3 in this example) are the large-diameter hard material layers 4L and the large-diameter hard material layers 4L. The larger the radial length of the stepped portions 4LM (in this example, the stepped portions 4LM1, 4LM, and 4LM3) located on the outer peripheral side than the paired small-diameter hard material layers 4S (in this example, the length L1<L2 <L3), it is preferable that the flexural rigidity is high. That is, in this example, it is preferable that the flexural rigidity increases in the order of the large-diameter hard material layers 4L1, 4L3, and 4L3 (large-diameter hard material layers 4L1<4L2<4L3). As a result, it is possible to further suppress curling up.
In the example of FIG. 6, among the plurality of pairs 4P, the large-diameter hard material layers 4L1, 4L2 and 4L3 have different flexural rigidity. The size relationship may be arbitrary. For example, as in the example of FIG. 6, the radial lengths L1, L2, and L3 of the stepped portions 4LM1, 4LM2, and 4LM3 of each pair 4P are longer (i.e., , length L1<L2<L3), the bending stiffnesses of the large-diameter hard material layers 4L1, 4L2 and 4L3 may be the same. Alternatively, the large-diameter hard material layers 4L1 and 4L2 may have the same bending rigidity, or the large-diameter hard material layers 4L2 and 4L3 may have the same bending rigidity.

In each example described in this specification, the laminated structure 3 has, as in each example of FIGS. has an outer diameter equal to or larger than the outer diameter of another hard material layer 4 adjacent to the hard material layer 4 on the inner side in the axial direction (that is, the outer diameter of each hard material layer 4 is the outer diameter in the axial direction). gradually increasing toward ) is preferred. In other words, the laminated structure 3, as in each example of FIGS. It is expedient if it does not have an outer diameter less than the outer diameter of another hard material layer 4 which is adjacent to it axially inwardly. As a result, compared to the case where any one of the hard material layers 4 has an outer diameter smaller than the outer diameter of the other hard material layer 4 adjacent to the hard material layer 4 on the inner side in the axial direction, The buckling resistance performance of the seismic isolation device 1 can be improved.
In addition, in each example described in this specification, the laminated structure 3 has a plurality of hard material layers 4 positioned most axially outward on at least one of its upper and lower ends, Each of the hard material layers 4 has an outer diameter larger than the outer diameter of the other hard material layers 4 adjacent to the hard material layer 4 in the axial direction (that is, the outer diameters of the plurality of hard material layers 4 are It is preferable that it always increases smoothly toward the outside without becoming constant in some areas). In this case, in addition to being able to improve the buckling resistance performance and the seismic isolation performance of the seismic isolation device 1, it is possible to further suppress the lamination structure 3 from being turned up.
1 to 3, in the laminated structure 3, a plurality of hard material layers 4 may have the same diameter in the central portion in the axial direction of the laminated structure 3, or In the central portion of the structure 3, a plurality of hard material layers 4 each have an outer diameter larger than the outer diameter of another hard material layer 4 adjacent to the hard material layer 4 axially inward (i.e., The outer diameters of these plurality of hard material layers 4 may always increase smoothly toward the outside in the axial direction without becoming constant in some areas. For example, in the laminated structure 3, in the entire axial direction of the laminated structure 3, a plurality of hard material layers 4 are arranged so that the outer diameter of the other hard material layer 4 adjacent to the hard material layer 4 on the inner side in the axial direction is increased. (that is, the outer diameters of these hard material layers 4 always increase smoothly toward the outside in the axial direction without becoming constant in some areas).
In these cases, the small-diameter hard material layer 4S of each pair 4P can become the large-diameter hard material layer 4L of another pair 4P adjacent to the pair 4P on the inner side in the axial direction. Similarly, the large-diameter hard material layer 4L of each pair 4P can be the small-diameter hard material layer 4S of another pair 4P adjacent to the pair 4P in the axial direction outside.

In each example described in this specification, the laminated structure 3 has a pair 4P consisting of a small-diameter hard material layer 4S and a large-diameter hard material layer 4L on at least one of its upper and lower ends. , as in the example of FIGS. 4 and 6, it is preferable that the radial length of the stepped portion 4LM of each pair 4P is longer as it is positioned further outward in the axial direction. As a result, it is possible to further suppress curling up of the laminated structure 3 compared to the case where the radial lengths L of the stepped portions 4LM of each pair 4P are the same as in the example of FIG.

1 to 3, each hard material layer 4 and each soft material layer 5 of the laminated structure 3 are not annular but solid, and the central axis O of the laminated structure 3 Although the hard material layer 4 and the soft material layer 5 are located thereon, the present invention is not limited to this. For example, the laminated structure 3 is configured such that each hard material layer 4 and each soft material layer 5 are annularly formed, and the central hole of each hard material layer 4 and the central hole of each soft material layer 5 form a laminated structure. The body 3 has an axially extending central hole on its central axis O, in which a columnar body may be arranged. It is preferable that the columnar body be configured to absorb vibration energy by plastic deformation. The pillars can be made of, for example, lead, tin, tin alloys, or thermoplastic resin.

The seismic isolation device of the present invention is designed to suppress the transmission of earthquake tremors to structures (for example, buildings such as buildings, condominiums, detached houses, warehouses, bridges, etc.). It is preferred when placed between structures.

1: seismic isolation device, 21: upper flange plate (flange plate), 22: lower flange plate (flange plate), 3: laminated structure, 4: hard material layer, 4S, 4S1 to 4S3: small diameter hard material layer ( hard material layer), 4L, 4L1 to 4L3: large diameter hard material layer (hard material layer), 4LM, 4LM1 to 4LM3: step portion, 41, 42: hard material layer, 4P, 4P1 to 4P3: pair, 5: soft material layer, 6: coating layer, O: center axis

Claims (6)

A seismic isolation device comprising a laminated structure having hard material layers and soft material layers alternately laminated in the vertical direction,
The laminated structure has a small-diameter hard material layer, which is the hard material layer, and is adjacent to the small-diameter hard material layer on at least one of its upper and lower ends in the axial direction outside. a large-diameter hard material layer that is the hard material layer having a larger diameter than the small-diameter hard material layer,
The large-diameter hard material layer has higher flexural rigidity than the small-diameter hard material layer or the hard material layer having a smaller diameter than the large-diameter hard material layer,
Any one of the large-diameter hard material layers is a seismic isolation device, wherein the thickness in the axial direction is larger than that of the hard material layers adjacent to the one of the large-diameter hard material layers axially outward. The seismic isolation device according to claim 1, wherein the large-diameter hard material layer has an axial thickness greater than that of the small-diameter hard material layer or the hard material layer having a smaller diameter than the large-diameter hard material layer. The material constituting the large-diameter hard material layer has a Young's modulus larger than that of the material constituting the small-diameter hard material layer or the material constituting the hard material layer having a diameter smaller than that of the large-diameter hard material layer. A seismic isolation device according to claim 1 or 2. The laminated structure has a plurality of pairs of the small-diameter hard material layer and the large-diameter hard material layer on at least one end side of an upper side and a lower side thereof,
Among the plurality of large-diameter hard material layers included in the plurality of pairs, at least a step in the large-diameter hard material layer located on the outer peripheral side of the small-diameter hard material layer paired with the large-diameter hard material layer The large-diameter hard material layer having the maximum radial length of the portion is the small-diameter hard material layer paired with the large-diameter hard material layer, or the hard material having a smaller diameter than the large-diameter hard material layer. The seismic isolation device according to any one of claims 1 to 3, wherein the bending rigidity is higher than that of the layer. The laminated structure has a plurality of pairs of the small-diameter hard material layer and the large-diameter hard material layer on at least one end side of an upper side and a lower side thereof,
Each of the large-diameter hard material layers of at least two of the plurality of pairs has higher bending rigidity than the small-diameter hard material layer paired with the large-diameter hard material layer. A seismic isolation device according to any one of the paragraphs. The plurality of large-diameter hard material layers included in the at least two pairs are formed at a stepped portion of the large-diameter hard material layer located on the outer peripheral side of the small-diameter hard material layer paired with the large-diameter hard material layer. The seismic isolation device according to claim 5, wherein the larger the radial length, the higher the bending rigidity.

Images