JP2884965B2 - Damping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping device for damping the vibration of a building.

[0002]

2. Description of the Related Art As a damping device linked to earthquake resistance in the event of a large earthquake, there is a damping device provided between two buildings, or between each structure having a double structure of one building. . This device provides a larger damping force than other devices. That is, for example, as other devices, a passive device using an additional mass of about 1% of the weight of a building or a device having an active dynamic vibration absorber is known.
The damping force is the inertial force of the additional mass (product of mass and acceleration) as a reaction force, and the weight of the additional mass that can be installed on the roof of a building is limited, so the power of the damping is also limited. There will be. However, in the damping device provided between the two buildings or the like, since the damping force is a reaction force between the inertial force and the rigidity of both buildings, a large damping force can be obtained with a relatively small device displacement.

Further, as an improvement of the damping device provided between two buildings, the two buildings are not directly connected with a damper or the like, but are connected via a lever or the like.
There is one that amplifies the relative vibration amplitude of two buildings and transmits it to a damper (Japanese Patent Application No. Hei.
-208238).

FIG. 4 shows an example of a damping device having such a lever. That is, the fulcrum 3 of the lever 2 is provided in one building 1, the operating point 5 of the lever 2 is provided in the other building 4, and the damper 7 is provided at the power point 1 of the lever 2. In this way, lever 2
The damping force can be increased without increasing the damping coefficient.

That is, focusing on one of the two buildings 1 and 4, the mass of the building is m, the damping coefficient is c,
If the stiffness is k and the amplitude is x, the equation of motion is mx × ″ + c × x ′ + k × x = 0 (1). The amplitude of this wave gradually decreases and attenuates along the time axis, and the rate at which the amplitude decreases becomes larger as the next attenuation constant h increases. Are known.

[0006]

(Equation 1) Here, in order to increase the damping force c · x ′ in the former expression (1), the normal damping coefficient c may be increased. However, for systems with rigidity ko, a large damping coefficient c
, The material has a large rigidity k at the same time depending on the material.

Therefore, if lever 2 is used, the damping coefficient c.x '
X 'alone can be increased. Therefore, the damping coefficient c does not have to be very large, so that it is not necessary to have a large rigidity k, and h in the latter equation (2) can be increased. In this way, effective damping can be performed by using the lever 2.

[0008]

However, when the two buildings vibrate relative to each other, the lever 2 becomes oblique (FIG. 4), and the distance a between the fulcrum 3 and the operating point 5 changes by a small amount Δa. I will. That is, the lever ratio b / a is (b + Δa) / (a−
Δa). Thus, when the lever ratio changes, the ratio of amplifying the relative amplitude between the two buildings by the lever changes, and x ′ changes, and thus the damping force c ·
x 'also changes. However, the optimal damping force is the mass ratio μ = m ₂ / m _{1 of} the _two buildings 1 and 4, and the rigidity ratio α = k
_The value is determined by ₂ / k ₁ (the mass and stiffness of the two buildings 1 and 4 are m ₁ and m ₂ and k ₁ and k ₂ , respectively). The effect of attenuating is reduced.

The present invention has been made to solve the above problems, and when two buildings are connected by a lever and a damper is attached, the damping device does not change its lever ratio even in the case of vibration. The purpose is to provide.

[0010]

In order to achieve the above object, the damping device of the present invention connects two buildings or each structure having a double structure of one building with one lever. And
One building or one structure has a lever fulcrum, the other has a lever action point, and a damper is attached to the lever force point, and the fulcrum base is in a direction substantially orthogonal to the input direction to the lever. It is characterized by being slidably supported.

[0011]

[Function] In the case of vibration, the fulcrum base slides and displaces with respect to the building in accordance with the relative vibration of the two buildings, so that the distance between the fulcrum and the point of action is kept constant, so that the distance between the fulcrum and the power point is also constant. To keep.

[0012]

1 and 2 show one embodiment of the present invention. FIG. 1 is a plan view showing a roof when two buildings 1 and 4 provided in parallel are viewed from the sky. The two buildings 1, 4
They are connected by one lever 2. That is, one building 1 is provided with a fulcrum 3 of a lever 2, and the other building 4 is provided with an operating point 5 of the lever 2. The fulcrum 3 is mounted on a fulcrum base 8 so as to be rotatable in a horizontal plane as shown in FIG. The fulcrum base 8 is supported by the building 1 via a roller 9 or a linear bearing and is slidable. The direction of the slide is substantially perpendicular to the input direction of vibration to the lever 2 (vertical direction in the figure) (horizontal direction in the figure).
It is. A damper 7 is attached to the power point 6 of the lever 2 between the lever 1 and the building 1.

The operation of this embodiment will be described below.
When the two buildings 1 and 4 perform relative vibration (vertical vibration in the figure) due to an earthquake or the like, the lever 2 rotates around the fulcrum 3.
With this rotation, the relative distance a between the fulcrum 3 and the action point 5 tends to change. That is, when the lever 2 is inclined with the rotation, the distance a tends to increase, and the lever 2 receives a pulling force. With this pulling force, the fulcrum base 8 slides smoothly on the roller 9 and moves in the left-right direction in the figure. The actual distance a between the fulcrum 3 and the point of action 5 does not change at all by the sliding movement. Therefore,
The remaining part of the lever 2, ie, the distance b between the fulcrum 3 and the power point 6
Does not change at all. Therefore, the lever ratio b / a is constant without any change due to vibration, that is, rotation of the lever 2. For this reason, the rate at which the relative amplitude between the two buildings 1 and 4 is amplified is constant, and the amplified amplitude x '(accurately, speed) can always be a constant optimal size, and the attenuation Force c x '
(Equation (1)) can be maintained at the value of the optimal damping force.

As a result, the lever ratio b as in the prior art (FIG. 4)
It can be prevented that the damping force c · x ′ changes due to the change of / a, and the damping effect of the building decreases.

By amplifying x 'in this manner, the damping force c.x' can be increased without increasing the damping coefficient c. Therefore, it is possible to prevent the material having the large damping coefficient c from having the large rigidity k to reduce the damping constant h (Equation (2)) and reduce the damping effect.

The lever 2 of the first embodiment has a linear shape, and the vibration to be attenuated was in a direction perpendicular to the two buildings 1 and 4 arranged in parallel (vertical direction in the figure). As shown in FIG. 3 showing the embodiment, the lever 2 and the damper 7 are arranged in a z-shape, and the direction of the damped vibration is the same as the direction in which the two buildings 1 and 4 are juxtaposed (lateral direction in the figure). be able to. That is,
The lever body 21 is disposed obliquely in one building 1. The fulcrum 3 of the lever body 21 is mounted on the fulcrum base 8, and the fulcrum base 8 is slidably supported on the building 1 as in the first embodiment. The direction of the slide is a direction perpendicular to the direction in which vibration is input to the lever 2 (horizontal direction in the figure) (vertical direction in the figure). An arm 11 is rotatably provided at an action point 5 of the lever body 21, is supported by the building 1 via a sliding support portion 12, and the other end is provided in the other building 4. The damper 7 is attached to the power point 6 of the lever main body 21. With this configuration, the relative vibration between the two buildings 1 and 4 is input to the lever 2 in the left-right direction in the figure,
The vibration in the left and right direction is damped.

Although the arm 11 is slidably supported in the second embodiment, the slidable support is stopped, and the other end of the arm 11 is rotatably provided on the other building 4 so that the arm 11 can be rotated. Two perpendicular directions (ie, vertical and horizontal directions in the figure)
Can be simultaneously attenuated. This is because vibrations in either direction tend to rotate the lever 2 and are damped by the damper 7. Even in such a case, the fulcrum base 8 can slide and maintain the value of the optimal damping force.

In the above embodiment, the lever 2 (or the lever body 2) is used.
Although the action point 5 is provided at the end of 1) and the fulcrum 3 and the fulcrum base 8 are provided at the center side, in other embodiments, these positional relationships may be reversed. In this case, the fulcrum base 8 is
(Or lever body 21) is slid. Originally, the names of the “fulcrum” and “action point” are for convenience, and the two cannot be distinguished.

[0019]

As described above, according to the damping device of the present invention, when the fulcrum base slides with respect to the building during vibration, the distance between the fulcrum and the point of action and the distance between the fulcrum and the force point are constant. , The rate at which the relative amplitude between the buildings is amplified is constant, and therefore, the value of the optimal damping force can be fixed and constant, and the building can be effectively damped. .

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view showing a second embodiment of the present invention.

FIG. 4 is a plan view showing a conventional example.

[Explanation of symbols]

 1,4 building 2 lever 3 fulcrum 5 point of action 6 point of force 7 damper 8 fulcrum base 9 roller 11 arm

Claims (1)

(57) [Claims] 1. A structure in which two buildings or one structure having a double structure of one building are connected by one lever, and one building or one structure has a lever fulcrum and the other has a lever fulcrum. A damping device comprising: a lever acting point; a damper attached to a lever force point; and the fulcrum supported by a fulcrum base in a direction substantially perpendicular to an input direction to the lever.