JPS61189342A - Damper - Google Patents

Abstract

PURPOSE:To improve the damper characteristics in order to ease absorption of vibrational energy by absorbing the vibrational energy through the hysteresis loss caused when a vibrational energy absorbing member, which is interposed between the foundation and a structure, undergoes the shearing deformation. CONSTITUTION:A damper 25, which is interposed between a foundation 27 and a structure 28, is constituted by covering a metallic rod 29, serving as a vibration absorbing member, with piled, doughnut-shaped rings 31, as sliding members together with installation of guide bars 33 around these doughnut- shaped rings 31. Due to sliding of these doughnut-shaped rings 31, the force acting on the space between the foundation 27 and the structure 28 is transmitted to the metallic bars 29. Thus, the shearing deformation of these metallic bars 29 is ensured. As a result, the vibration of the structure 28 is absorbed by the hysteresis loss caused by the said shearing deformation.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention constitutes a vibration isolation device interposed between a foundation and a structure, and absorbs vibration energy during an earthquake to suppress vibration of the structure. Regarding the damper.

[Technical background of the invention and its problems]

Generally, structures such as plant equipment are attached to a device composed of an elastic body and a damper. This vibration isolation device absorbs the forces acting between the foundation and structures during earthquakes, etc.
Vibration is suppressed.

6 and 7 show the vibration isolation devices 1 and 2, and FIG. 6 shows the friction damper 3 as a damper and the vibration damper 7 as a damper.
The figures each employ a viscous damper 5.

Generally, the elastic body 7 absorbs the force acting on the structure 11 from the foundation 9 during an earthquake or the like. Also,
The dampers 3 and 5 absorb the vibration energy of the structure 11 that occurs after this acting force is absorbed by the elastic body 7, and dampen the vibration of the structure 11. moreover,
The dampers 3 and 5 control the amount of deformation of the elastic body 7 to prevent damage to the elastic body 7 itself when an excessive force is applied to the elastic body 7, and also prevent the structure 11 and the foundation 9 from being damaged. This is to avoid damage to piping, etc. installed between the two.

However, the friction damper 3 shown in FIG. 6 may have some disadvantages in damper characteristics. In other words, friction damper 3
The characteristic curve depicts a hysteresis loop as shown in FIG. 8(A), but this hysteresis loop is an acute angle loop. Therefore, the friction damper 3 cannot smoothly absorb the vibration energy of the structure 11 at point a, which exhibits maximum displacement under maximum load, and harmonics may occur in the structure at point a. Therefore, structure 1
There is a possibility that it may have an adverse effect on the equipment etc. installed in 1.

On the other hand, in the viscous damper 5 shown in Fig. 7, the damper characteristic curve draws a rounded and smooth hysteresis loop as shown in Fig. 8 (B), so the damper characteristics are good, but the damper structure The disadvantage is that it is complicated and maintenance is troublesome. Further, the viscous damper 5 has a large damper and occupies a large space, and since the amount of displacement of the damper is large, a large space is required to accommodate this displacement. Therefore, such a viscous damper 5 has the disadvantage that the installation space increases.

[Purpose of the invention]

This invention was made in consideration of the above facts,
Has good damper characteristics and absorbs vibration energy smoothly.
The object of the present invention is to provide a damper having a simple and compact structure.

[Summary of the invention]

In order to achieve the above object, the damper according to the present invention has the following features:
In those that constitute a vibration isolation device that absorbs the acting force between foundations and structures during earthquakes and suppresses vibrations,
Provided so that it can be interposed between the foundation and the structure, and
It has a vibration energy absorbing member and is configured to absorb vibration energy through hysteresis loss during shear deformation of the vibration energy absorbing member.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a sectional side view showing a vibration isolator to which a first embodiment of a damper according to the present invention is applied.

As shown in FIG. 1, the vibration isolation device 21 is composed of an elastic body 23 and a damper 25, and absorbs the force acting between the foundation 27 and the structure 28 during an earthquake, thereby suppressing vibration.

Among these, the elastic body 23 is composed of laminated rubber or the like,
It is bolted to the foundation 27 and the structure 28, respectively. Therefore, when the foundation 27 moves horizontally during an earthquake, the force acting on the structure 28 from the foundation 27 is transferred to the elastic body 2.
It is absorbed by the deformation of No. 3, and the structure 28, piping, etc. are protected.

On the other hand, as shown in an enlarged view in FIG. 2, the damper 25 covers a metal rod 29 as a vibration energy absorbing member with a stacked donut-shaped ring 31 as a sliding member. A guide rod 33 is installed on the outer periphery of the guide rod 33. Roughly, metal rod 29
The stacked donut-shaped rings 31 are abutted and supported by an upper support plate 35 and a lower support plate 37.

The upper support plate 35 and the lower support plate 37 are integrally connected by the guide rod 33.

The metal rod 29 is made of a soft metal such as lead or a lead alloy, and when the metal rod 29 is sheared as shown in FIG. Draw a hysteresis loop as shown in figure (C). The vibration energy of the structure 28 that occurs after the acting force between the foundation 27 and the structure 28 is absorbed by the elastic body 23 is absorbed by hysteresis loss during shear deformation of the metal rod 29, and the vibration of the structure 28 is attenuated. be done. Furthermore, by absorbing this vibration energy, the amount of deformation of the elastic body 23 is controlled even when an excessive force is applied to the elastic body 23.

The donut-shaped ring 31 is then stacked around the metal rod 29 and configured to cover the metal rod 29.

Each donut-shaped ring 31 is slidably provided as shown in FIG. A shear deformation of 29 is ensured. Also,
The inner diameter of the donut-shaped ring 31 is formed to be approximately the same as the outer diameter of the metal rod 29. As a result, the donut-shaped ring 3
1 slides, force is smoothly transmitted from the donut-shaped ring 31 to the metal rod 29, and uniform shear deformation is applied to the metal rod 29 without bending stress.

The guide rod 3 is attached to the upper support plate 35 and the lower support plate 37.
Through-holes 39A and 39B are drilled through the holes 3, respectively. These through holes 39A and 39B are formed with tapers that expand in diameter in opposing directions.

This taper prevents the guide rod 33 from coming into contact with the upper and lower support plates 35, 37 when the guide rod 33 moves as shown in FIG. Also,
The through hole 39B formed in the lower support plate 37 has a substantially hemispherical shape at the lower portion of the chi 1 shown in FIG.

The guide rod 33 is passed through the through holes 39A and 39B. The lower end of the guide rod 33 is formed into a spherical shape, and the through hole 39B
A spherical joint is formed by contacting the inner hemispherical surface. Further, the upper end portion of the guide rod 33 projects above the through hole 39A, and is supported by the upper support plate 35 via a nut 41, a washer 43, and a spring 45. Natsuto 4
1 is screwed onto the upper end of the guide rod 33, and this nut 41
A spring 45 is interposed between the upper support plate 35 and the upper support plate 35 with a washer 43 interposed therebetween. In the operating state of the damper 25 shown in FIG. 3, a change in the length of the guide rod 33 between the upper and lower support plates 35, 37 is allowed by the expansion and contraction of the spring. Furthermore, the upper and lower support plates 35 and 37 are
An integral connection via the guide rod 33 is always ensured.

Further, three guide rods 33 are provided at equal intervals around the stacked donut-shaped rings 3-1, and are provided in close contact with the outer periphery of the stacked donut-shaped rings 31. This guide rod and stacked donut-shaped ring 3
1 , the acting force between the base 1227 and the structure 28 is transmitted to the stacked toroidal rings 31 via the guide rod 33 . Further, the guide rod 33 is made of a highly rigid material. Therefore, this guide rod 3
3 is not damaged by the acting forces between the foundation 27 and the structure 28, which are transmitted to the guide rod via the upper and lower support plates 35.37.

A connecting rod 47 is integrally formed on the upper support plate 35 .

This connecting rod 47 is provided so that it can be fitted into the cylinder portion of a connecting cylinder 49 fixed to the structure 28 . Further, the lower support plate 37 is provided so as to be fixable to the foundation 27 with foundation bolts 53.

Next, the effect will be explained.

When an earthquake etc. occurs, the foundation 27 moves horizontally, and this foundation 2
7, a force based on an earthquake or the like acts on the structure 28. However, this acting force is absorbed by the deformation of the elastic body 23 itself, and damage to the structure 28 and piping connected to this structure is avoided.

On the other hand, after the elastic body 23 absorbs the acting force from the foundation 27, vibrations occur in the structure 28. The force associated with this vibration is
It is transmitted from the structure 28 to the upper support plate 35 via the connecting cylinder 49 and the connecting rod 47. Furthermore, the acting force from this structure 28 is transferred from the upper support plate 35 to the guide rod 33.
is transmitted to the stacked donut-shaped rings 31 via. Then, this stacked donut-shaped ring 3
1 slides as shown in FIG. 3, and due to this sliding, the metal rod 29 is sheared and deformed as shown in the same figure. As the structure 28 vibrates, when forward and reverse acting forces are repeatedly applied to the metal rod 29, the metal rod 29 is displaced in a hysteresis loop shown in FIG. 8(C). The vibration energy of the structure 28 is absorbed by hysteresis loss during shear deformation of the metal rod 29, and as a result, the vibration of the structure 28 is attenuated.

In this way, the vibration energy of the structure 28 is absorbed by the hysteresis loss during shear deformation of the metal rod 29, but the hysteresis loop of the metal rod 29 is shown in FIG.
Since it is a rounded and smooth curve as shown in C),
By the damper 25 equipped with this metal rod 29, the structure 2
-8 vibration energy is absorbed smoothly. Therefore, the characteristics of the damper 25 are good, and harmonics etc. are not generated in the structure 28, and a suitable damping effect can be achieved. As a result, the vibration of the structure 28 can be reliably suppressed, and there will be no adverse effect on the II device installed in the structure 28.

Further, even when an excessive force is applied from the foundation 27 to the structure 28 during an earthquake, the damper 25 absorbs the vibration energy of the structure 28, so that the displacement of the elastic body 23 can be controlled. As a result, the elastic body 23 may be damaged due to an increase in the relative displacement between the structure 28 and the foundation 27, and the foundation 27 may be damaged.
Also, damage to piping etc. installed between the structures 28 can be prevented.

Moreover, the metal rod 29 is covered with the laminated donut-shaped rings 31, and the metal rod 29 is covered by the sliding of the donut-shaped rings 31.
Since the force is transmitted to the metal rod 9, uniform elastic deformation can be caused in the metal rod 29. therefore,
The metal rod 29 is not damaged due to local stress caused by bending, and the reliability of the damper 25 can be improved.

Further, the damper 25 has donut-shaped rings 31 stacked around the metal rod 29, supported at the top and bottom by an upper support plate 35 and a lower support plate 37, and these upper and lower support plates 35 and 37 are supported by a guide rod 33. Since it is integrally connected, the structure is simple and maintenance can be performed easily.

Further, since the damper 25 itself is small and the displacement force of the damper 25 is small, the installation space for the damper 25 including the space for allowing the damper to be displaced can be reduced. Therefore, the space can be used effectively, and the damper 25 is particularly suitable for use in a narrow space.

4 and 5 are explanatory diagrams showing a second embodiment of the damper according to the present invention. In this second embodiment, parts similar to those in the first embodiment are designated by the same reference numerals, and a description thereof will be omitted.

In the damper 25 of the first embodiment, three guide rods 33 are provided, but in the damper 55 of the second embodiment, eight guide rods 33 are provided. These eight guide rods 33
are placed close to the outer periphery of the stacked donut-shaped rings 31 at equal intervals. Therefore, the force acting on the damper 55 from the structure 28 is applied to these eight guide rods 33.
is transmitted to the stacked donut-shaped rings 31. Here, the reason for increasing the number of guide rods is to prevent damage to the guide rods 33 when the acting force from the structure is excessive. Therefore, the number of guide rods 33 and the degree of their rigidity are optimally set depending on the magnitude of the acting force from the structure 28.

In the first and second embodiments, the metal rod 29 is made of a soft metal such as lead, but it may also be made of a resin such as hard rubber.

〔Effect of the invention〕

As described above, according to the damper of the present invention, the vibration energy absorbing member is interposed between the foundation and the structure, and the hysteresis loss during shearing deformation of the vibration energy absorbing member is Since it absorbs vibration energy, it has good damper characteristics, can absorb vibration energy smoothly, and has a simple and compact structure.

[Brief Description of the Drawings] Fig. 1 is a sectional side view showing a vibration isolator to which a first embodiment of a damper according to the present invention is applied, and Fig. 2 is a sectional side view showing an enlarged view of the damper of the first embodiment. 3 is a sectional side view showing the operating state of the damper of the first embodiment, FIG. 4 is a side view showing the second embodiment of the damper according to the present invention, and FIG. 5 is a plan view of the second embodiment. 6 is a side view showing a conventional vibration isolator using a friction damper, FIG. 7 is a side view of a conventional vibration isolator using a viscous damper, and FIG. 8 is a characteristic curve of the damper. (
A> is a conventional friction damper, (B) is a conventional viscous damper,
(C) is a graph showing each characteristic curve of the damper according to the first embodiment of the present invention. 21... Vibration isolation device, 25... Damper, 27... Foundation, 28... Structure, 2... Metal rod, 31...
Donut-shaped ring, 33... Guide rod, 35... Upper support plate, 37... Lower support plate.

Claims (1)

[Claims] 1. A damper that constitutes a vibration isolation device that absorbs acting forces between the foundation and the structure during an earthquake and suppresses vibration, which can be interposed between the foundation and the structure. established,
A damper comprising a vibration energy absorbing member and configured to absorb vibration energy through hysteresis loss during shear deformation of the vibration energy absorbing member. 2. The damper according to claim 1, wherein the vibration energy absorbing member is made of soft metal. 3. The vibration energy absorbing member is covered with a sliding member that is slidable in the vibration direction, and by the sliding of this sliding member,
3. The damper according to claim 1, wherein the acting force between the foundation and the structure is transmitted to the vibration energy absorbing member to ensure shear deformation. 4. The damper according to claim 3, wherein the slide member is a plurality of stacked donut-shaped rings. 5. The energy absorbing member is in contact with the foundation and the structure through the support plate, and the guide rod disposed between these support plates allows the acting force between the foundation and the structure to be absorbed by the vibration energy through the slide member. A damper according to claim 3 or 4, which is transmitted to a member.