JPH01125442A - Earthquakeproof and vibrationproof device - Google Patents

Abstract

PURPOSE: To improve base isolation performance and vibration resistant performance by providing elastic members on an upper surface of an upper supporting plate and a lower surface of a lower supporting plate of an air spring, by arranging each elastically supporting body the elastic members on a place where at least a triangular point is formed, and by locating a shaft axis of the air spring in an area of the point. CONSTITUTION: An air spring 21 is so constituted that compressed air is enclosed in an air chamber 26 sealed with an upper supporting plate 23 and a lower supporting plate 25, and at least oscillates in a perpendicular direction. Elastic member 30, 32 are provided on an upper surface of an upper supporting plate 23 and a lower surface of a lower supporting plate 25 of the air spring 21, and each elastically supporting body of the elastic members 30, 32 is arranged on three place where at least a triangular point is formed. A shaft axis of the air spring 21 exists in an area where those points are produced. Thereby, excellent base isolation and vibration resistant performance can be obtained against vibration of a perpendicular and horizontal directions, and since an allowable range of a horizontal direction grows, a base isolation and vibration resistant device prevented buckling can be obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a seismic isolation/vibration isolation device that has sufficient seismic isolation/vibration isolation performance in three-dimensional directions and has a large permissible displacement in the horizontal direction. .

[Conventional technology]

Conventionally, as a seismic isolation/vibration isolation device for two structures such as buildings,
As shown in FIG. 4, a structure is known in which an air spring device in which an air spring 3 and a laminated rubber 8 are connected in series is arranged and fixed between a foundation 1 and a support 2. The air spring 3 is of a diaphragm type in which an air chamber 7 is formed between an outer cylinder 4 and an inner cylinder 5 by an annular flexible rubber membrane 6, and the laminated rubber 8 is made of a rubber plate 9 having elasticity. It has a structure in which rigid plates 10 made of metal or the like are alternately laminated and bonded.

The seismic isolation device shown in Fig. 5 and Fig. 6 is known as multi-layered rubber (Japanese Patent Laid-Open No. 61-143).
(Refer to Publication No. 40), elastic supports 12 having a structure in which an upper laminated rubber 12a and a lower laminated rubber 12b are stacked in at least two stages in the height direction are arranged at at least three points forming the vertices of a triangle, and each elastic The overlapping portions of the supports 12 are fixed by one rigid connecting member 13.

[Problem that the invention seeks to solve]

Among conventional seismic isolation devices, the air spring device shown in Figure 4 has seismic isolation performance against three-dimensional vibrations in the horizontal (front, rear, left and right) and vertical directions, but it has a lightweight structure with a small supporting load. When used for seismic isolation of objects, the laminated rubber 8 must have an elongated shape in order to satisfy the required horizontal spring characteristics, which makes it difficult to simultaneously secure both the required horizontal spring constant and the required horizontal allowable displacement. When a large horizontal displacement occurs, there is a problem that the pressure receiving area of the laminated rubber 8 decreases and buckling occurs.

On the other hand, in the multi-stage laminated rubber shown in FIG. 5, the rotation of the elastic support 12 at the center is restrained by the connecting member 13, and the pressure receiving area against horizontal displacement increases, so even if a large horizontal displacement occurs, each laminated rubber 12a remains unchanged.

12b does not buckle and has the performance that satisfies both the required spring constant and required allowable displacement in the horizontal direction, but it has a structure in which the laminated rubber 12a and 12b are stacked in the height direction. Therefore, the spring characteristics in the vertical direction are hard, and therefore, when used as a seismic isolation device in the vertical and horizontal three-dimensional directions, there is a problem that satisfactory performance cannot be obtained.

This invention solves the above problems and has sufficient seismic isolation and vibration isolation performance in three-dimensional directions, and even when the permissible horizontal displacement is large and the supporting load is small, the required spring constant in the horizontal direction and the required The purpose is to provide a seismic isolation/vibration isolator that can satisfy both the permissible displacement and the permissible displacement.

[Means for solving problems]

The seismic isolation/vibration isolator of the present invention includes compressed air sealed in an air chamber sealed by an upper support plate and a lower support plate, an air spring member that is swingable at least in the vertical direction, and an upper part of the air spring member. It is composed of an upper elastic member and a lower elastic member, each of which is a plurality of elastic supports fixed to the upper surface of the support plate and the lower surface of the lower support plate.

Each of the elastic supports of the upper elastic member and the lower elastic member is provided at least at three locations forming the vertices of an equilateral triangle, and the axial center of the air spring member is located within the area connecting the vertices. It is arranged.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the invention, and the basic 1
The seismic isolation/vibration isolator of the present invention is installed between the base and the support 2.

The air spring member 21 is of the same type as the diaphragm-type air spring shown in FIG. The air chamber 26 is formed into a rectangular shape and is formed between the outer cylinder 22 and the inner cylinder 24 via a diaphragm-shaped rubber 825.
This communicates with an auxiliary air chamber 29 inside the inner cylinder 24.

The upper support plate 23 and the lower support plate 25 are formed from rigid metal plates.

An upper elastic member 30 made of four laminated rubber 30a is arranged on the upper surface of the upper support plate 23 of the air spring member 21, and a lower elastic member 30 made of four laminated rubber 32a is similarly arranged on the lower surface of the lower support plate 25. A member 32 is provided.

The laminated rubber 30a constituting the upper elastic member 3o and the laminated rubber 32a constituting the lower elastic member 32 have a length DP of one side centered on the axial center of the air spring member 2I.
Each center axis line coincides with the vertical line passing through the vertices of the square with pitch).

Pressure receiving plates 31a and 31b are fixed to the upper and lower surfaces of each laminated rubber 30a of the upper elastic member 30, and this pressure receiving plate 31a
, 31b are the lower surface of the support body 2 and the air spring member 21, respectively.
The upper surface of the upper support plate 23 is fixed to the upper surface of the upper support plate 23. Further, pressure receiving plates 3 are provided on the upper and lower surfaces of each laminated rubber 32a of the lower elastic member 32.
3a, 33b are fixed, and these pressure receiving plates 33a, 33b are fixed to the lower surface of the lower support plate 25 of the air spring member 21 and the upper surface of the foundation l, respectively.

Each of the laminated rubber 30a, 32a of these upper and lower elastic members 30, 32 has a structure in which disk-shaped rubber plates 34 and rigid plates 35 are alternately laminated and bonded, similar to the laminated rubber shown in FIG. Real cylindrical body, each laminated rubber 30a, 32
The effective height H2 and effective outer diameter DR□ of a are the same size.

When an earthquake occurs, the seismic isolation/vibration isolator having the above configuration becomes horizontally displaced as shown in FIG.

A comparison of the operation of the apparatus according to the embodiment shown in FIG. 1 and the conventional apparatus shown in FIG. 4 during horizontal displacement is as follows.

First, in the conventional device, the horizontal spring constant of the air spring 3 is KA, the horizontal spring constant of the laminated rubber 8 is KA, the laminated rubber 8 is
Let Hl and DIl be the effective height and effective outer diameter of
+, horizontal displacement x2 of the load force center P with respect to the laminated rubber 8
Consider the allowable amount. X is the sum of the horizontal displacement xR of the laminated rubber 8 and 1/2 of the relative displacement XA between the inner cylinder 5 and outer cylinder 6 of the air spring (x.

=x, l+xA/2), xR+xA is the displacement of the entire device
However, when the load force center P exceeds the end point A of the laminated rubber 8, the laminated rubber 8 begins to buckle. Therefore, the horizontal displacement allowable amount XACPI is D+++/2.

In contrast, the air spring member 21 in the device of the invention shown in FIG. 1 has the same horizontal spring constant KA as the conventional air spring 3.
The upper and lower elastic members 30 and 32 have horizontal spring constants, and l is 1/1 of that of the conventional laminated rubber 8.
2, the laminated rubber 30a.

If it is configured with four 32a, the horizontal spring constant of the entire device will be equivalent to that of the conventional device.

Therefore, the permissible horizontal displacement of the load force center P for the upper elastic member 30 will be considered. The horizontal displacement xp+ of the load force center P on the upper elastic member 30 is determined by the displacement XRI of the laminated rubber 30a and the relative displacement x between the inner cylinder 5 and the outer cylinder 6 of the air spring, as in the conventional case.
It becomes 1/2 of A. When the load force center P exceeds point A of the laminated rubber 30a, the laminated rubber 30a buckles, so the allowable displacement amount from this point is (Dr + D11□)/2. On the other hand, since multiple upper elastic members are arranged, the buckling point of each laminated rubber is the point where the center of force on the laminated rubber exceeds point A, and the allowable displacement from this point is DR2. .

From this, the allowable displacement amount is determined by the smaller of (Dr + D11□)/2 or Do, but usually Dr, l! Since it is larger, the allowable displacement is I) mz
becomes. Of course, also for the lower elastic member 32, the allowable horizontal displacement of the horizontal displacement xrz of the load force center P is Do. The permissible horizontal displacement of the upper and lower elastic members 30.32 is therefore 2D++t.

As mentioned above, in order to make the horizontal spring constant of the entire device in Figure 1 equivalent to that in Figure 3, the horizontal spring constant of the laminated rubber should be 1/2 that of the laminated rubber in Figure 3. However, for this purpose, for example, each of the upper and lower laminated rubber 30a
, 32a may be set to 1/2 of the effective height HI of the conventional laminated rubber 8, and the pressure receiving area may be set to 1/4. In this case, the effective diameter, l□, becomes 172 of DI+.

From now on, the permissible displacement position of the device of this invention, X ACP! is, XAcpt=2D++t=2X D+++=2°X
With the device of the invention, expressed as ACFI, twice the horizontal displacement is obtained by the upper and lower elastic members 30, 32 compared to a conventional device with an equivalent horizontal spring constant.

Also, if H7 is the same as H8, the effective diameter D
1 beam, //2', and in this case, a horizontal displacement 2L times greater than that of the conventional device can be obtained.

In addition, in FIG. 3, xA is the horizontal displacement of the air spring member 21, and X is the horizontal displacement of the entire device.

Furthermore, when comparing the prying spring constants of the upper and lower elastic members of the device of the present invention and the laminated rubber of the conventional device, it is found that the conventional device has a /2), whereas in the device of this invention, it is the sum of the product of the upper and lower spring constants and (Dr/2)'' for each laminated rubber. The spring constant is greater than the laminated rubber of conventional devices.

Therefore, in the device of the present invention, the angle of inclination of the upper support plate 23 and lower support plate 25 of the air spring member 21 becomes smaller when horizontal displacement occurs.

In the above embodiment, the case was explained in which four pieces of laminated rubber 30a of the upper elastic member 30 and four pieces of laminated rubber 32a of the lower elastic member 32 were arranged. It is sufficient that there are at least three, and in either case, the air spring member 21 is arranged such that the axial center of the air spring member 21 is within a region connecting the vertices of a triangle or polygon.

Further, a bellows-type air spring may be used instead of the diaphragm-type air spring shown in the above embodiment as the air spring member 21, and the air spring is not limited to the air spring that can swing vertically and horizontally. It is also possible to use an air spring member, such as an air cylinder, having an air chamber that is swingable only in this direction.

Further, for the laminated rubber 30a, 32a constituting the upper and lower elastic members 30, 32, anti-vibration rubber or other elastic supports can also be used.

〔Effect of the invention〕

As explained above, according to the present invention, not only sufficient seismic isolation and vibration isolation performance can be obtained against three-dimensional vibrations in the vertical and horizontal directions, but also the permissible displacement in the horizontal direction is increased. It is possible to obtain a seismic isolation/vibration isolating device that does not sag and also satisfies the required horizontal displacement amount by designing the horizontal spring constant of the elastic support body to be small when the supporting load is small.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the invention, and FIG. 2 is a side view showing an embodiment of the invention.
A sectional view taken along line A-A in the figure, Figure 3 is a side view showing the operating state of the seismic isolation/vibration isolator shown in Figure 1 during horizontal displacement, and Figure 4 shows the conventional air spring device and the operating state during horizontal displacement. FIG. 5 is a side view showing a conventional multi-layer laminated rubber, and FIG. 6 is a sectional view taken along the line V-■ in FIG. 5. In the figure, 20 is a seismic isolation/vibration isolator, 21 is an air spring, 23 is an upper support plate, 25 is a lower support plate, 26 is an air chamber, 30 is an upper elastic member, 30a is a laminated rubber, and 32 is a lower elastic member. , 32a is a laminated rubber, and D is a pinch of the laminated rubber.

Claims (1)

[Claims] Compressed air is sealed in an air chamber sealed by an upper support plate and a lower support plate, and an air spring member that can freely swing at least in the vertical direction, and an upper surface of the upper support plate of the air spring member and a lower surface of the lower support plate of the air spring member. comprising an upper elastic member and a lower elastic member made up of a plurality of fixed elastic supports, each of the elastic supports of the upper elastic member and the lower elastic member being provided at at least three locations forming the vertices of a triangle;
A seismic isolation/vibration isolating device characterized in that the air spring member is arranged such that its axial center lies within a region connecting the vertices of the air spring member.