JPH0334505Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to a hydraulic vibration isolator that seismically supports supported objects such as piping systems in nuclear power plants and the like.

"Prior Art" As a conventional hydraulic vibration isolator, there is one shown in FIG. 5, for example. This means that the oil chambers 31a and 31b on both sides of the cylinder 31 are communicated through an oil feed pipe 32, and a poppet valve 33 and an oil tank 34 are connected in the middle of the oil feed pipe 32.
It has been established. In this case, when the supported body vibrates and the piston rod 35 is suddenly moved in and out of the cylinder 31, the poppet valve 33 closes the oil passage due to hydraulic resistance and restricts the movement of the piston rod 35. This provides an anti-vibration effect. Slow movement of the piston rod 35 due to thermal displacement of the supported body is allowed without the poppet valve 33 operating. The oil tank 34 is
Based on the difference in volume between the oil chambers 31a and 31b on both sides of the piston 36, excess or deficiency in the amount of oil flowing in and out between the oil chambers 31a and 31b on both sides, which occurs when the piston 36 moves, is adjusted.

"Problems that the invention attempts to solve" In the conventional hydraulic vibration isolator mentioned above, the oil tank 3
4 is provided separately from the cylinder 31, and these are connected to each other by the oil pipe 32,
Many seals are formed, and oil leaks are likely to occur from these. In addition, there were other problems such as the device becoming larger and requiring a large installation space.

The present invention aims to solve the above-mentioned conventional problems and provide a hydraulic vibration isolator that is compact and has a structure that is less likely to cause oil leakage.

"Means for Solving the Problems" In the present invention, in order to solve the above-mentioned conventional problems, the lid 3 at one end of the cylinder 1 is composed of an upper lid 3a and a lower lid 3b, and there is a gap between the two lids 3a and 3b. An oil tank 4 is formed on the outer periphery of the piston rod 6, and this oil tank 4 is attached to the lower lid 3b of the cylinder 1.
An oil passage 3d communicating with one of the oil chambers 1a is provided, and a poppet valve 5 is interposed in the oil passage 3d to prevent rapid flow from the oil chamber 1a to the oil tank 4. As a result, an oil passage 7a is provided that communicates the two oil chambers 1a and 1b divided within the cylinder 1, and poppet valves 8 and 8 are installed in the oil passage 7a to prevent rapid flow into the oil chambers 1b and 1a. A hydraulic vibration isolator was constructed by interposing the

[Effect]

The oil tank 4 is provided integrally with the cylinder 1,
Yes for externally facing seals. When the piston rod 6 moves in and out slowly due to thermal displacement of the supported body, the oil in both oil chambers 1a and 1b flows into the oil passage 7.
It flows freely and slowly through the piston rods a and 3d without being obstructed by the poppet valves 8 and 5, and the movement of the piston rod 6 is not obstructed.

On the other hand, when the supported body is about to displace rapidly due to an earthquake or the like, the poppet valve 8 or 5 closes the oil passage due to hydraulic resistance, and the piston rod 6
The vibration of the supported body is controlled by restricting the movement in and out of the support body.

That is, when the supported body tries to rapidly displace to one side, the piston 7 is pushed to one side and one oil chamber 1
The oil pressure at b increases, and one poppet valve 8 closes the oil passage to cut off the flow of oil. Conversely, when the supported body attempts to displace to the other side, the oil pressure in the other oil chamber 1a increases, and the poppet valve 5 and the other poppet valve 8 respectively close the oil passages and cut off the flow of oil. In this way, vibrations in both directions are suppressed.

"Example" The cylinder 1 has a handle 2a on the outside of the lower end lid 2, which is connected to a supported body. The upper end lid 3 of the cylinder 1 has a double structure consisting of an upper lid 3a and a lower lid 3b, and the upper and lower lids 3a and 3b are connected to each other by a connecting tube 3c through which a piston rod 6 passes. An oil tank 4 is formed between the upper and lower lids 3a and 3b.

An oil passage 3d is formed in the lower lid 3b, and the oil tank 4 is supplied through a poppet valve 5 provided therein.
It communicates with one oil chamber 1a inside the cylinder 1.

The piston rod 6 is attached to the upper end cover 3 of the cylinder 1.
It extends upwardly and slidably through it, and its upper end is connected to a support such as a construct.

The piston 7 has two oil chambers 1 inside the cylinder 1.
It is divided into a and 1b. The piston 7 is formed with an oil passage 7a that communicates the two oil chambers 1a, 1b, and has a pair of poppet valves 8, 8 disposed in opposite directions.

The tie rod 9 tightens the lower end lid 2 of the cylinder 1, and the bearing stress between the cylinder 1 and the upper end lid 3 improves sealing performance.

Next, the operation of this embodiment will be explained.

When a supported body such as a piping system connected to the handle 2a of the cylinder 1 undergoes thermal displacement, a slow relative movement occurs between the cylinder 1 and the piston rod 6. In this case, the oil in the oil chambers 1a, 1b on both sides slowly flows through the oil passage 7a without operating the poppet valves 8, 8, allowing displacement of the supported body. The volumes of both oil chambers 1a and 1b differ from each other by the volume occupied by the piston rod 6. Therefore, when the piston rod 6 moves relative to each other, the amount of oil that moves differs between the oil chambers 1a and 1b. Any excess or deficiency in the inflow or outflow of oil is compensated for by the flow of oil into and out of the oil tank 4.
In other words, the volume of oil occupied by the piston rod 6 is
The oil flows freely and slowly within the oil passage 3d of the lower lid 3b without being obstructed by the poppet valve 5.

On the other hand, when the supported body is about to vibrate rapidly due to an earthquake or the like, the poppet valve 8 or 5 closes due to hydraulic resistance caused by the sudden movement of oil, stopping the movement of oil and causing the relative movement of the piston rod 6. is restrained. This suppresses the vibration of the supported body. That is, when the supported body tries to rapidly displace downward in FIG. 2, the piston 7 is pushed downward and the oil pressure in the lower oil chamber 1b increases, and the lower poppet valve 8 closes the oil passage 7a and drains the oil. block the distribution of Conversely, when the supported body tries to displace upward, the oil pressure in the upper oil chamber 1a increases, and the poppet valve 5 and the upper poppet valve 8 close the respective oil passages 3d and 7a, blocking the flow of oil. do. In this way, vibrations in both directions are suppressed.

In the other embodiment shown in FIG. 3, one end lid of the cylinder 1 is constituted by separate upper and lower lids 13a and 13b, and the volume of the oil tank 14 is increased.

Still another embodiment shown in FIG. 4 is installed horizontally, and the lid 23 is modified so that the oil level in the oil tank 24 is always above the cylinder 1.

"Effect of the invention" As mentioned above, in this invention, cylinder 1
Since the one end lid 3 has a double structure of upper and lower lids 3a and 3b, and the oil tank 4 is formed there, there is no sealing part and there is no fear of oil leaking to the outside. Also,
This made it possible to reduce the size and weight.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram of the present invention, Fig. 2 is a longitudinal sectional front view, Fig. 3 is a longitudinal sectional front view of a part of another embodiment, Fig. 4 is a longitudinal sectional front view of yet another embodiment, and Fig. 5 is a longitudinal sectional front view of a part of another embodiment. The figure is a diagram of the principle of a conventional example. 1... Cylinder, 1a, 1b... Oil chamber, 2, 3
...Lid, 2a...Handle, 4...Oil tank, 5...
...Poppet valve, 6...Piston rod, 7...Piston, 7a...Oil passage, 8...Poppet valve.

Claims (1)

[Claims for Utility Model Registration] A cylinder that is connected to the supported body via a handle on the outside of the lid at one end; The other end of the cylinder has an upper lid and a lower lid, and an oil tank is formed on the outer periphery of the piston rod between the two, and the oil tank is connected to the lower lid. An oil passage is provided to communicate the oil to one oil chamber in the cylinder, and a poppet valve is interposed in this oil passage to prevent rapid flow from the oil chamber to the oil tank, and the piston is connected to one oil chamber in the cylinder. The oil pressure is divided into two oil chambers, and an oil passage is provided to communicate the two oil chambers, and a poppet valve is interposed in the oil passage to prevent rapid flow to each oil chamber. Vibration isolator.