JPH05256048A - Vibration damper - Google Patents

Abstract

PURPOSE:To obtain a vibration damper applicable to a structure having a short vibratory frequency. CONSTITUTION:A plurality of curved rails 2 shaped as an arc recession-form are arranged in series with the vibratory direction of a structure. Wheels 4 are provided at the lower face of a vibration damper 5 to correspond to the curved rails 2. The vibration damper 5 is placed on the curved rails 2 through the wheels 4. When a vibration is brought on the structure 1, the vibration damper 5 oscillates through the rotary movement of the wheels 4 to prevent the structure 1 from oscillating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is attached to the upper part of a structure such as a tower of a suspension bridge, a super high-rise building, a tower, a steel tower, etc. to suppress the vibration of these structures due to wind load (aerodynamic force) and the vibration amplitude due to an earthquake. The present invention relates to a vibration damping device used to quickly damp vibrations.

[0002]

2. Description of the Related Art A vibration damping device of this kind is designed to reduce the vibration of a structure by converting the shaking energy applied to the structure into the kinetic energy of a weight and efficiently damping it. Has been proposed (JP-A-2-102945). This is a development of a simple pendulum, and as shown in the outline of FIG.
Is placed on a support roller c installed on the structure b so as to be curved in an arc shape so as to perform single-string vibration, and a rack d is placed on the upper surface of the vibration damping body a along the vibration direction.
Further, a shaft e arranged so as to be orthogonal to the rack d is connected to a motor f at an upper part of the rack d, and a pinion g is attached to an intermediate part of the shaft e so as to mesh with the rack d. The motor f is driven to rotate the pinion g via the shaft e so that the damping body a can be moved together with the rack d in a required cycle.

According to the vibration damping device proposed in Japanese Unexamined Patent Publication No. 2-102945, when the structure b is shaken by aerodynamic force or the like, the motor f drives the structure b 90 times against the shake. The kinetic energy for performing the single-string vibration is applied to the vibration-damping body a with a delay, and the energy is applied to the structure b in the optimum state, so that the vibration of the structure b can be suppressed quickly. It is a thing.

[0004]

However, in the case of a single-string vibration type vibration damping device using the above-mentioned arc-shaped vibration damping body a,
Although the vibration cycle is determined by the radius of the vibration damper a,
Since the movement amount is restricted within a range that does not deviate from the support roller c, the radius cannot be set too small. Therefore, there is a problem that it cannot be used for a structure having a short vibration period. Further, in the case of a vibration damping device of the type in which the vibration damping body a is vibrated by a single string, it is better to install the driving device, devices attached thereto, and parts on the vibration damping body a in terms of the entire plane space. Although it is advantageous in that the damping mass can be added to the damping body a to reduce the size of the damping body a itself, the damping body a is formed in an arc shape. It is difficult to install a driving device or the like.

Therefore, the present invention is intended to provide a vibration damping device which can be applied to a structure having a short vibration period and in which a driving device and the like can be installed on a vibration damping body.

[0006]

In order to solve the above-mentioned problems, the present invention arranges a plurality of curved rails formed in a concave arc shape in series along the vibration direction of a structure, and on the curved rails. In addition, a damping body having wheels on its lower surface corresponding to the curved rail is mounted via the wheels.

[0007]

When the structure shakes, the vibration is transmitted to the curved rail, and the vibration suppressor is oscillated with a delay of 90 °. Therefore, the energy given to the vibration control body is given so as to suppress the swing of the structure. At this time, since the vibration damper is mounted on the curved rail via the wheels, the bending radius of the curved rail can be freely selected, and the vibration damping body can be applied to a structure having a short vibration cycle.

[0008]

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

FIG. 1 and FIG. 2 show an embodiment of the present invention. Two curved rails 2 formed in a concave arc shape are provided on a structure 1 whose vibration is to be suppressed through a pedestal 3, A rectangular parallelepiped damping body 5 in which two lines are laid in series along the vibration direction of the structure 2 and wheels 4 are provided on the lower surface of the curved rail 2 corresponding to the series pitch P of the curved rail 2. To
The vibration damping body 5 is mounted via the wheels 4 and is configured to be swingable in the left-right direction in FIG. 1 through the rolling of the wheels 4 along the curved rail 2 direction.

Although not shown, stoppers also serving as dampers for restricting the swing stroke of the vibration damper 5 are provided at both ends of the vibration damper 5 in the rocking direction.

Now, when the structure 1 shakes due to aerodynamic force, an earthquake, or the like, the shake is suppressed passively by the vibration damper 5. That is, since the shaking energy generated in the structure 1 is transmitted to the curved rail 2 via the gantry 3, the curved rail 2 is integrated with the structure 1 as shown in FIG.
Will swing to the left and right. At this time, since the vibration control body 5 is swingable with respect to the curved rail 2 via the wheels 4, the vibration control body 5 oscillates like a single-string vibration in the left-right direction with a delay of about 90 ° with respect to the vibration of the structure 1. Start moving. Therefore, the swing motion of the vibration damper 5 is applied in a direction that cancels the swing of the structure 1, so that the swing of the structure 1 is quickly suppressed.

In the above description, since the vibration damper 5 is only placed on the curved rail 2 via the wheel 4, it can move freely even if the radius of the arc of the curved rail 2 is small or large. .. At this time, the vibration control body 5 can always be horizontally held and stably rocked without tilting regardless of the radius of the curved rail 2. Therefore, by selecting the radius, it is possible to apply to both a structure having a short vibration period and a structure having a long vibration period.

Next, FIG. 3 shows another embodiment of the present invention. Since the vibration damper 5 can be oscillated while keeping horizontal, a drive unit is installed on the vibration damper 5 to suppress the vibration. The body 5 can be driven semi-actively. That is, in the same configuration as shown in FIG. 1 and FIG.
A rack 6 curvedly formed in parallel with the curved rail 2 is fixedly provided at a position between the upper curved rails 2, and a pinion 7 meshing with the rack 6 is supported by a wheel shaft 8 and the wheel shaft 8 is also supported.
A chain wheel 9 is attached to one end of the motor 10, while a motor 10 and a speed reducer 11 are provided as drive devices on the vibration damper 5.
Is installed, a chain wheel 13 is attached to the output shaft 12 of the speed reducer 11, and a chain 14 is hung between the chain wheel 13 and the chain wheel 9,
By transmitting the driving force of the motor 10 to the pinion 7 that meshes with the rack 6 via the chain wheel 13, the chain 14, the chain wheel 9, and the wheel shaft 8, the damping body 5
It is designed to be able to swing.

In the case of the embodiment shown in FIG. 3, the vibration of the structure 1 is effectively damped by oscillating the damping body 5 by 90 ° out of phase with the vibration of the structure 1 by driving the motor 10. Can be made At this time, when the vibration damping body 5 is swung by the motor 10, the vibration damping body 5 is subsequently swung.
The vibration damping effect can be obtained by simply actuating the vibration damper 5 semi-actively with a small control force. Further, in the case of the embodiment shown in FIG. 3, since the motor 10, the speed reducer 11 and the like as the drive device are installed on the damping body 5, the entire plane surface is smaller than that when the drive device is installed on the fixed side. It is advantageous in terms of space, and further, since the drive device is added to the mass of the vibration damper 5, the vibration damper 5 itself can be downsized.

In the above embodiment, the case where the two curved rails 2 are arranged in series has been shown, but it is also possible to have three or more rails. In the embodiment of FIG. 3, the motor 10 is driven. The case where a power transmission mechanism including a chain wheel and a chain is used to transmit the force to the pinion 7 is shown, but a gear transmission mechanism or the like may be used, and other within the scope not departing from the gist of the present invention. Of course, various changes can be made.

[0016]

As described above, the vibration damping device of the present invention exhibits the following excellent effects. (1) Since the damping body is mounted on the curved rails arranged in series via the wheels so that it can be swung freely, the radius of the curved rail can be freely selected. It can also be applied to a long structure, and can quickly suppress the sway of the structure. (2) Since the vibration damper can swing without tilting, it is possible to install a drive device or the like on the vibration damper, which is advantageous in terms of the overall flat space.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an embodiment of a vibration damping device of the present invention.

FIG. 2 is a cut side view of FIG.

FIG. 3 is a cut side view showing another embodiment of the present invention.

FIG. 4 is a schematic diagram showing an example of a conventional vibration damping device.

[Explanation of symbols]

 1 structure 2 curved rail 4 wheel 5 damping body

Claims (1)

[Claims] 1. A plurality of curved rails formed in a concave arc shape are arranged in series along a vibration direction of a structure, and wheels are provided on the curved rails on a lower surface portion corresponding to the curved rails. A vibration damping device having a configuration in which a vibration damping body is mounted via the wheels.