JPS6138355Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a seismic vibration isolation device for pipe busbars.

When performing seismic design of pipe busbars, in order to ensure a necessary and sufficient safety factor for support devices, especially insulators, the acceleration response multiple of pipe busbars to earthquake input is reduced, and the load applied to the insulators is reduced. It is effective to reduce this.

Generally, in order to reduce the acceleration response magnification of a structure, it is necessary to increase the damping constant.

The damping constant of an aluminum pipe busbar is normally around 2%, and when combined with a support frame and insulator, the acceleration response magnification can reach 20 times. For this reason, a vibration isolator is installed on the pipe busbar,
If the damping constant of the pipe is increased to about 15%, the acceleration response magnification can be reduced by 7 to 8 times. This leads to the ability to reduce the strength of the pipe support device, making it possible to economically design the support device.

Conventionally, as shown in FIG. 1, this kind of vibration isolator has been equipped with a support part 2 provided inside a pipe bus bar 1, and a weight 4 provided at both ends of a stranded wire 3 attached to this support part 2. However, in the above structure, as shown below: (1) Since the natural frequency is determined by adjusting the length of the stranded wires, the strands are deflected and the margin of movement is narrow.

(2) Since stranded wires are used, wire breakage occurs.

(3) The weight of the vibration isolator collides with the inner wall of the pipe bus bar, causing a collision sound, damage to the weight, and deformation of the pipe.

(4) Due to (2) and (3), the lifespan of the vibration isolator is short.

There are drawbacks such as.

The present invention provides an earthquake-resistant and vibration-isolating device for pipe busbars that eliminates the above-mentioned drawbacks. The feature of this vibration isolator is that it uses multiple pendulums installed coaxially with the pipe inside the pipe to vibrate the weight and create a reaction force, and the vibration phase shift between the pendulum components prevents the surfaces from sliding against each other. We decided to obtain a damping effect by using two methods.

An embodiment of the seismic vibration isolation device for pipe busbars of the present invention will be described based on FIG. 2. In the figure, A is a front view and B is a side view.

and are first and second weights, respectively, which are rigid pendulum elements, and the first weight is supported by a core rod and fixed to the pipe by a support fitting. In addition, the second weight is suspended from a part of the first weight by the core rod, and the first weight moves around the core rod, and the movement of the core rod thereby causes the second weight to move. Make the weight vibrate. In order to adjust the rotation angle and natural frequency of the first weight, one end of a spring (for example, a spirally wound piano wire) may be fixed to the first weight and the other end to the support. good.

When the pipe busbar vibrates in the horizontal direction due to an earthquake, the core rod moves in the same direction as the pipe busbar because the vibration isolator support part is fixed to the pipe busbar at the vibration isolator attachment part by plug welding or screw fastening. The response of the first and second weights is delayed due to their inertia, and eventually they produce pendulum motion around the center line of the pipe. This movement causes friction between the core rod and the weight, between the core rod and the weight, and between the weight, producing a vibration-proofing effect.

The free damping vibration when the vibration isolator of this invention is installed on an aluminum pipe busbar with a pipe busbar size of φ250mm x t10mm and a span of 18m is as shown in Figure 3B.
This shows better characteristics than the free damped vibration of the pipe busbar without the vibration isolator in A.

The effects of the seismic vibration isolator for pipe busbars of the present invention are as follows: (1) Since it is installed coaxially with the pipe busbar, the vibration isolator does not collide with the inner wall of the pipe busbar;
No deformation or damage.

(2) The vibration isolator is a physical pendulum, and the natural frequency is determined by the moment of inertia, the distance between the fulcrum and the center of gravity, and the spring constant of the spring, so vibration suppression of the pipe busbar system can be easily adjusted.

(3) Since multiple pendulums are used, the vibration effect between the pendulums becomes large, and if the natural frequencies of the pendulums are slightly different, the vibration phase shifts, further increasing the damping effect.

etc.

As described above, the seismic vibration isolation device for pipe busbars of the present invention has great practical effects when applied to aluminum pipe busbars and copper pipe busbars in power generation and substations.

[Brief explanation of drawings]

Fig. 1 is a side sectional explanatory view of a conventional seismic vibration isolator for pipe busbars, and Fig. 2 is an explanatory view of the seismic vibration isolator for pipe busbars of the present invention, where A is a front sectional view and B is a side view of A. , Figure 3 is an explanatory diagram of the effect when the vibration isolator of the present invention is installed on the pipe busbar, where A shows the free damped vibration of the pipe busbar when there is no vibration isolator, and B shows the free damped vibration of the pipe bus when the vibration isolator is installed. It is a characteristic diagram. 1...first weight, 2...second weight, 3...
Core rod, 4...Core rod, 5...Supporting part, 6...Pipe, 7...Spring,...Fixing part,...Weight,...Twisted wire.

Claims (1)

[Scope of claims for utility model registration] (1) A support part that supports a core rod inside the pipe bus bar,
a first weight pivotally connected to the core rod at a distance; and a first weight between the first weights and the first weight
An earthquake-resistant pipe busbar comprising: a second weight pivotally attached to a core rod fitted to the weight; and a spring inserted between the first weight and the support part. Anti-vibration device. (2) The core rod supported by the support part and the core rod fitted to the first weight are each parallel to the central axis of the pipe generatrix.Claim 1 of Utility Model Registration
Earthquake-resistant vibration isolation device for pipe busbars as described in . (3) The seismic vibration isolation device for a pipe busbar according to claim 1 or 2, wherein the interval provided between the first weight is such that sliding wear occurs between the second weight and the second weight. .