JPH0419440A - Vibration damping device - Google Patents

Abstract

PURPOSE:To decrease vibration of a structure by arranging a swivel frame, comprising a plurality of struts and a lower part structural member turnably connected to a lower end of the strut, in an upper part of the structure so as to make it possible to perform a parallelogram motion and further mounting a weight onto the concerned lower part structural member. CONSTITUTION:Since energy of a shake is transmitted to a weight 7 via outer and inner side frames 3, 4 when the shake is generated in a structure 1, the weight 7 starts a simple harmonic motion with a 90 deg. delay from the shake of the structure 1 through the swivel displacement of the frame 4. Accordingly, the shake of the structure is suppressed by the weight 7 acting as a vibration damping mass for giving force in an opposite direction to force coming into the structure 1. Here, vibration energy of the weight 7 is diffused unless it is controlled, so that the shake of the structure 1 can be promptly suppressed to within a permissible range by arbitrarily controlling the simple harmonic motion of the weight 7 performed through a reduction gear 18, shaft 10 and the inner side frame 4 by forwardly/reversely driving a motor 17 based on a signal output from a phase control unit.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention can be attached to the top of a structure such as a suspension bridge tower, a skyscraper, a tower, or a steel tower.
The present invention relates to a vibration damping device used to suppress vibrations caused by fl load Φ (aerodynamic force) and vibration amplitude caused by strata to quickly damp vibrations.

[Prior Art] Conventionally, as a vibration damping device for this type of structure, for example, as shown in FIG. The structure is such that a liquid such as water is quickly poured into the tank C as required, and the sloshing phenomenon occurs when the shaking of the structure a is caused by the liquid d in the tank C moving from side to side without passing through the wire mesh. [Hilding Tower J
(published in December 1988), and a text entitled "Technological Development of Vibration Control and Seismic Isolation Structured Buildings" at the Japan Building Center Information Exchange Seminar on New Building Structural Technology (Showa 6).
(October 2003, published by the Japan Building Center Foundation)] or, as shown in Figure 7, on the top of structure a,
A laminated rubber e formed by laminating multiple layers in the vertical direction is installed, and a weight f is supported on the upper end of the laminated rubber e, and the vibration of the structure a is transferred to the weight f via the laminated rubber e. Some proposals have been made to dampen vibrations by vibrating.

[Problem to be solved by the invention 1 However, among the conventional methods described above, in the case of the example shown in FIG. 6 in which the liquid d in the tank C is sloshed, (1) The liquid d is used as a weight for vibration damping. Because of this,
The size of the entire device must be increased; ■ It is difficult to move liquid d in tank C through a wire mesh or change its attenuation rate; There are problems such as the difficulty in tuning the natural period of In the case of the example shown in the figure, (1) Since the weight f is supported by the laminated rubber e, the mass of the device should not be made too large; ■ Since the damping rate is determined by the laminated rubber, Things that can be changed but cannot be changed, Value It is difficult to synchronize the natural period of the device itself with the natural period of the structure a, O Laminated rubber e deteriorates, so the life is short, and ω It is not possible to obtain a large amplitude. There are other problems.

Therefore, the present invention attempts to solve the problems of the above-mentioned conventional methods and reduce the vibration of the structure by converting the vibration energy given to the structure into the kinetic energy of the weight and efficiently damping it. It is something to do.

[Means for Solving the Problems 1] In order to solve the above-mentioned problems, the present invention provides a structure in which the upper part of the structure includes a plurality of support columns and a lower structural member rotatably connected to the upper end of each branch. A swinging frame is arranged so as to be able to perform parallelogram motion, a weight is attached to the lower structural member of the swinging frame, and a spring is attached to a support column facing the movement direction of the swinging frame. A plurality of spring locking portions are provided so that the position can be arbitrarily changed in the vertical direction, and the springs are arranged diagonally and locked between the opposing spring locking portions.

In addition, in the case of an active vibration damping device, the structure includes an actuator for controlling the movement of the swing frame from the outside.

Furthermore, in the case of a passive vibration damping device, a damper for damping the motion of the swinging frame may be connected to the outside of the swinging frame or installed diagonally between the branches of the swinging frame. shall be.

[Operation] When shaking energy is applied to a structure, the swinging frame including the weight or a single string is photographed with a delay of 90 degrees to the structure.
The weight can be used as a damping mass. The vibration period of the weight can be matched to the natural period of the structure by changing the locking position of the spring.

Further, when an actuator is connected to the swing frame to form an active type, a vibration damping effect can be obtained by applying the driving force of the actuator as a control force.

Historically, when a passive type damper was installed on a swinging frame, the energy of the structure was consumed by the attenuator via the swinging frame, making it impossible to effectively suppress the shaking of the structure. can.

[Implementation Example 1] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the present invention, in which a heath 2 is provided on the top of a structure 1 that vibrates in response to external force,
An outer frame 3 is constructed by assembling a plurality of branches 5 erected on the base 2 and an upper structural member on the branches 5,
A plurality of struts 6 whose upper ends are rotatably supported by the upper structural members of the outer frame 3 and suspended, and lower structural members supported by the lower ends of the struts 6 are assembled so as to perform parallelogram motion. An inner frame 4 is configured as a swinging frame, and a weight 7 as a structure vibration damper is attached to the inner frame 4. When shaking occurs in the structure 1, the weight 7 or the inner frame 4 The shaking of the structure 1 can be suppressed by making it possible to vibrate in the left and right directions together with the structure 1.

To be more specific, four pillars 5 are erected and fixed at the front, rear, left and right positions on the base 2, and the upper ends of the opposing left and right branches 5 are attached to upper structural members so as to integrate the respective branches 5. The outer frame 3 is constructed by connecting the outer frame 3 by a horizontal member 8 as an upper structural member, and connecting both ends of the horizontal member 8 by a vertical member 9 serving as an upper structural member. Further, a shaft 10 disposed in the front-rear direction is rotatably supported by a bearing 11 between both ends of the front and rear cross members 8 of the outer frame 3, and the shaft 10 has a shaft 10 having a required length. The upper ends of the book branches 6 are attached so that they can rotate in the left and right directions through the rotation of the shaft 10, and the FEi of the opposing left and right columns 6 are used as lower structural members so as to integrate the branches 6. It is connected to the horizontal plate 12 via a hinge 13 so as to be rotatable in the left-right direction to constitute an inner frame 4 as a swinging frame. To be able to freely swing and displace like a quadrilateral link. Further, in the inner frame 4, a weight 7 having a large ratio Φ, such as lead, is fixed to the center of the horizontal plate 12, and the weight 7 is made like a pendulum that vibrates a single chord together with the inner frame 4. In order to make the vibration period of the plows 7 correspond to the natural period of the structure 1, a spring (a spring cylinder in the figure) is installed between the branches 6 facing each other in the left and right direction of the inner frame 4. 14 are arranged diagonally, and a hole 16 at a desired position is selected from among a large number of holes 16 serving as spring locking portions of a perforated plate 15 attached to each branch 6 along the vertical direction. The spring 14 is locked and tensioned. Furthermore, at one end of each shaft 10,
A motor 17 as an actuator for controlling the movement of the inner frame 4 is connected via a reducer 18, and the motor 17 and the reducer 18 are mounted on a pedestal 19 that projects from the upper side of the outer frame 3. to be installed. Incidentally, the motor 17 is designed to be driven in forward and backward directions based on a signal from a phase control device (not shown).

When the vibration damping device of the present invention having the above configuration is installed at the top of a structure 1 such as a tower, when shaking occurs in the structure 1 due to aerodynamic forces or earthquakes, the shaking energy is transferred to the outer frame. 3 and the inner frame 4 to the weight 7, the plow 7 starts a single string vibration 90 degrees behind the swing of the structure 1 through the swing displacement of the inner frame 4. Therefore, it is difficult to determine whether the weight 7 can act as a damping mass that applies a force in the opposite direction to the force entering the structure 1, and can suppress the shaking of the structure 1. Since the photographing energy key 7 will diverge if not controlled, the motor 17 is driven in forward and reverse directions based on the signal output from the phase control device. A single chord of the weight 7 (driven or arbitrarily controlled) is performed via the frame 4, and the swinging of the structure 1 can be quickly suppressed within an allowable range.In other words, the swinging of the structure 1 (The energy given to the weight 7 as a drive will diverge as described above unless a control force is applied, so by driving the motor 17, the amplitude that requires the weight 7 / Jl
It can provide control force to increase speed and braking force to suppress divergence.

In the above, the damping force to the structure 1 is the purchase amount of 70 weights,
It can be changed by selecting the imaging stroke. In this case, the plow 7 can be made of a material with a high specific gravity such as lead, and the plow 7 can be fixed on the horizontal plate 12 which is the lower structural material of the inner frame 4 to lower the center of gravity. Therefore, the entire device can be downsized and the installation space can be reduced. Also, inner frame 4
Since it is displaced to cause the movement of a parallelogram link, a large vibration stroke can be achieved. or,
From this, the weight of the weight 7 can be reduced.

Further, each column 6 of the inner frame 4 is provided with a perforated plate 15 having a large number of holes 16 for adjusting the spring force.
By selecting the positions of these holes 16 and adjusting the force of the spring 14, the natural period of the damping device itself can be easily synchronized with the natural period of the structure 1.

Next, FIG. 4 shows another embodiment of the present invention, in which a passive type is used instead of the active type in which the photographing of the weight 7 is controlled by driving the motor 11. It is. That is, the attenuator 20 is diagonally interposed between the opposing left and right columns 6 of the inner frame 4 so as to be parallel to the spring 14. The attenuator 20 may be an oil damper whose damping rate can be changed by changing the internal pressure (or an air damper whose damping rate can be changed by changing the internal air pressure). A damper, a spring that changes the damping rate by changing its length (spring force), etc. may be of any type such as liquid, gas, or mechanical force.

In the case of the embodiment shown in FIG. 4, since the swing of the inner frame 4 including the weight 7 is attenuated by the attenuator 20, it is possible to quickly suppress the swing of the structure 1 through indirect energy consumption. can. At the mouth, the attenuation rate is attenuator 20
It is possible to give the optimum condition by adjusting.

FIG. 5 shows still another embodiment of the present invention, in which structure 4
A recess 1a is provided in the upper surface of #11, and a swing frame 4' having the same structure as the inner frame 4 shown in the embodiment shown in FIGS. 1 to 3 is provided within this recess 1a. The swinging frame 4' is suspended and supported by the base 2 fixed on the recess 1a, and the swinging frame 4 is suspended and supported by the motor 17.
′ must be able to be actively swung. In FIG. 5, the same parts as in FIGS. 1 to 3 are given the same reference numerals.

In the case of the embodiment shown in FIG. 5, since the swing frame 4' is suspended from the base 2, there is an advantage that the outer frame 3 can be made unnecessary.

Note that the present invention is not limited only to the above-mentioned embodiments; for example, in the active type embodiments shown in FIGS. etc. are used as dampers, and in the case of hydraulic bomber water pumps, by changing the discharge rate and discharge pressure, and in the case of generators, by changing the field current or armature current, respectively. Ability to change rate arbitrarily or be passively configurable;
Further, although the embodiment shown in FIG. 5 shows the case where the swinging frame 4' is configured as an active type, it is also possible to configure it as a passive type such as the inner frame 4 shown in FIG. In the embodiment, an example of application to an architectural structure such as a tower is shown, but it is also possible to apply it to a mechanical structure such as a container crane or office equipment, and various changes may be made within the scope of the gist of the invention. Of course, it is possible to add

[Effect 1 of the Invention As described above, the vibration damping device of the present invention exhibits the following excellent effects.

1) Since it is possible to convert the swinging ball energy of the structure into the kinetic energy of the seven weights of the swinging frame that performs parallel rectangular motion, it is possible to control it with the seven weights, or to use an attenuator. By properly attenuating the structure, the shaking of the structure can be quickly suppressed.

(11) By selecting the tensioning position of the spring @8, the natural period of the object and the natural period of the damping device can be made to completely match each other, so a great damping effect can be obtained.

<1ii) Since the weight uses the principle of a pendulum, it is easy to move with little friction and provides reliable operation.

Since the weight can be made of a weight with a high specific gravity, it can be made compact, and the installation area of the entire device can therefore be reduced.

(V) Since it can have a large stroke and a large weight, it can also be used for large structures.

(vl) Due to its simple structure, maintenance is easy.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an outline of an embodiment of the vibration damping device of the present invention, Fig. 2 is a side view of Fig. 1, Fig. 3 is an east view of Fig. 1, and Fig. 4 is the invention of the present invention. FIG. 5 is a schematic diagram showing another embodiment of the present invention, and FIGS. 6 and 7 are schematic diagrams showing examples of conventional devices. be. 1... Structure, 2... Base, 3... Outer frame, 4... Inner frame (swinging frame), 4'...
・Swinging frame, 6... Support, 7... Throttle, 12.
-・Horizontal plate (lower structure material), 14...Spring, 1
6-...hole (spring locking part), 17...motor (
actuator), 20...attenuator. Figure 1 Figure 2

Claims (3)

[Claims] (1) A swing frame consisting of a plurality of columns and a lower structural member rotatably connected to the lower end of each column is arranged on the upper part of the structure so as to be able to perform parallelogram motion, and A weight is attached to the lower structural member of the swinging frame, and furthermore, a plurality of spring engagements are installed on the pillars facing the movement direction of the swinging frame so that the mounting position of the spring can be arbitrarily changed in the vertical direction. A vibration damping device characterized in that a stop portion is provided and a spring is disposed diagonally and locked between the spring lock portions facing each other. (2) The vibration damping device according to claim (1), further comprising an actuator for externally controlling the movement of the swing frame. (3) The vibration damping device according to claim (1), further comprising a damper for damping the movement of the swing frame.