JPH058084U - U-shaped vibration control tank device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a U-shaped vibration damping tank device having a simple structure and low cost, having no fear of strength, easily adjusting the frequency, and suitable for a large vibration damper. [Configuration] Vertical tanks 3a on the left and right of the U-shaped communication tank,
In the vibration damping tank 1 in which a liquid is filled with an air chamber left above 3b, a plurality of thin tubes each having a valve 7 inserted in the middle part thereof are used to form the left and right vertical tanks 3a, 3b.
A U-shaped vibration damping tank device in which air chambers of b are connected to each other.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a U-shaped vibration damping tank device.

[0002]

[Prior Art]

 2. Description of the Related Art A dynamic vibration reducer has been known as one of vibration isolating means for structures. As shown in FIG. 5, the basic structure of the dynamic vibration reducer is that the vibrator 010 is supported by the spring 011 and the support base 012, and the natural frequency thereof is determined by the mass of the vibrator and the elasticity of the spring 011. The application of this to the anti-sway tank mainly used in ships is shown in Fig. 6. That is, this figure is a vertical cross-sectional view, and the lower portions of the left and right vertical tanks 01a and 01b are connected by a communication pipe 06. Vent pipes 03a and 03b extending from the upper portions of the vertical tanks 01a and 01b are connected to a pressure air source (not shown) via valves 04a and 04b and air supply pipes 07a and 07b, respectively. After pressure air is sent from the pressure air source to the air chambers 05a, 05b on the liquid surfaces of the left and right vertical tanks 01a, 01b, the valves 04a, 04b are completely closed, and the air chambers 05a, 05b are independent of each other. It becomes an airtight chamber, and the pressure fluctuation of the air inside acts on the fluid surface in the vertical direction as the liquid level moves up and down, and acts as the force of the elastic spring, and acts as a damping function equivalent to that shown in FIG. . Therefore, if the natural frequency of the dynamic vibration absorber is made to match the vibration frequency of the structure by appropriately selecting the mass of the vibrator 010 and the rigidity of the spring 011, the dynamic vibration absorber can be operated as shown in FIG. The frequency of the structure changes from the characteristic shown by the broken line to that shown by the solid line, and the vibration reduction effect can be seen.

[0003]

[Problems to be solved by the device]

 However, the damping tank of this type of structure has the following problems. That is, (1) The amplitude of the oscillator becomes large and there is concern about the strength of the spring. (2) It is difficult to design and manufacture a spring mechanism for a large dynamic vibration absorber. (3) To adjust the vibration frequency, it is necessary to change the mass and spring rigidity of the vibrator, which is not easy to do with a large size. The present invention has been proposed in view of such circumstances, and provides a U-shaped vibration damping tank device which has a simple structure, is inexpensive, has no fear of strength, is easy to adjust, and is suitable for a large vibration damper. The purpose is to provide.

[0004]

[Means for Solving the Problems]

 To this end, the present invention is a vibration damping tank in which liquid is filled with air chambers above the left and right vertical tanks of a U-shaped communication tank. The feature is that the air chambers of the left and right vertical tanks are connected to each other.

[0005]

[Action]

 With such a configuration, the air in the air chambers of the left and right vertical tanks acts as an elastic spring against the left-right vibration of the liquid in the tank, thereby forming a vibration system. When the vibration frequency of the anti-vibration tank is adjusted to the vibration frequency by opening and closing the volume and static pressure of the air chamber and the thin tube valve of the air chamber, the action of the dynamic vibration absorber can be obtained. Vibration can be obtained even if the left and right vertical tanks are connected by a single thick pipe and the valve is installed in the middle to change the opening, but from the point of view of the site operation one can clearly be found. It is easier to accurately set the natural frequency of the tank when the narrow tube is opened and closed.

[0006]

【Example】

 1 is a longitudinal sectional view showing a first embodiment of the present invention, FIG. 2 is a graph showing the relationship between air chamber static pressure and frequency in FIG. 1, and FIG. FIG. 4 is a vertical sectional view showing a second embodiment of the present invention, and FIG. 4 is a vertical sectional view showing a third embodiment of the present invention. First, in the first embodiment shown in FIG. 1, the air chambers 4a and 4b are left above the vertical tanks 3a and 3b forming the left and right ends of the U-shaped tank 1, and the fluid 2 such as water is stored inside the tank 1. Stretch out. Here, the air chambers 4a, 4b are connected by a plurality of thin tubes 5 each provided with a valve 7 that can be opened and closed, and a pressure is applied to the air chambers 4a, 4b by a compressed air source (not shown). By combining this pressure, the opening and closing of the thin tube 5 by the valve 7 and the number thereof, the frequency can be adjusted in a wide range as shown in FIG. Next, in the second embodiment shown in FIG. 3, the thin tubes are inserted in parallel in the central part of the thick parent tube 6 which is discharged from both air chambers 4a and 4b. Further, the third embodiment shown in FIG. 4 shows an example in which each thin tube 5 is independently opened to the atmosphere without connecting the air chambers 4a and 4b. In this case, The static pressure of the air chambers 4a and 4b is atmospheric pressure, and the vibration frequency is adjusted by opening and closing the thin tubes.

[0007]

[Effect of the device]

 In each of these embodiments, the natural frequency of the left-right vibration of the liquid inside the communication tank is determined by the combination of the liquid amount, the static pressure of the air chamber, and the opening / closing of the thin tube. If this is selected as the required amount, adjusted to the required frequency, and installed in the structure to be vibration-isolated, it acts as a dynamic vibration absorber, and the effect of reducing the vibration of the structure can be obtained. In short, according to the present invention, in a vibration damping tank in which liquid is filled with air chambers left above the vertical tanks on the left and right of the U-shaped communication tank, a plurality of valves each having an intermediate portion are inserted. By connecting the air chambers of the above left and right vertical tanks with a thin tube, the structure is simple and the cost is low, there is no concern about strength, adjustment is easy, and a U-shaped control suitable for large vibration dampers is also available. Since the shaking tank device is obtained, the present invention is extremely useful in industry.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the air chamber static pressure and the frequency in FIG.

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

FIG. 4 is a vertical sectional view showing a third embodiment of the present invention.

FIG. 5 is a model diagram showing a known dynamic vibration reducer.

FIG. 6 is a vertical cross-sectional view showing a known U-shaped vibration damping tank for ships.

FIG. 7 is an explanatory diagram showing a damping effect in FIG.

[0008]

[Explanation of symbols]

 1 U-shaped tank 2 Fluid (liquid) 3a, 3b Vertical tank 4a, 4b Air chamber 5 Thin tube 6 Thick tube 7 Valve (valve)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Mamoru Matsuo 1-1 No. 1 Satinoura-cho, Nagasaki-shi Nagasaki Research Institute, Mitsubishi Heavy Industries, Ltd.

Claims (1)

[Claims for utility model registration] [Claim 1] A valve is inserted in the middle part of a vibration damping tank in which liquid is filled with air chambers left above the vertical tanks of the U-shaped communication tank. U-shaped vibration damping tank device, characterized in that the air chambers of the left and right vertical tanks are connected to each other by a plurality of thin tubes.