JPH0213787Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hydraulic vibration isolator having a mechanism for discharging gas generated in the oil inside the cylinder of the hydraulic vibration isolator to the outside.

A cylinder connected to a supported object such as a piping system is submerged in an oil case fixed to a support, and on both sides of it,
Two piston bodies that protrude opposite each other are inserted into the oil case, and a communication hole is provided in the two piston bodies to communicate between the inside and outside of the cylinder, and a check valve is interposed in this, so that by hydraulic action, The applicant has proposed a stationary hydraulic vibration isolator that allows slow displacement of the supported body due to thermal expansion or the like, but restrains sudden displacement due to earthquakes or the like.
In such hydraulic vibration isolators, if the oil in the cylinder becomes oxidized or is exposed to radiation,
It has been confirmed that chemical changes produce trace amounts of gas. However, if this gas accumulates in the cylinder, the supported body cannot be firmly restrained by hydraulic pressure.

The present invention was developed by focusing on the above-mentioned problems with conventional hydraulic vibration isolators.A piston ring is fitted into a piston that fits into a cylinder with the abutment facing upward, and the abutment It is an object of the present invention to solve the above-mentioned problems by discharging gas to the outside of the cylinder from a ventilation gap formed between the cylinder and the inner periphery of the cylinder.

Embodiments of the present invention will be described below with reference to the figures. The oil case 1 is fixed horizontally on a support S such as the floor of a building. A cover 3 having an opening 2 is mounted on the oil case 1. The oil case 1 contains hydraulic oil 0 such as silicone oil.

The cylinder 4 is submerged in hydraulic oil 0 within the oil case 1 and is horizontally movable. A partition wall 5 is provided at the center of the cylinder 4 to divide it into two parts. Thus, the cylinder 4 is attached to a holder 7 having a bracket 6 projecting upward from the oil case 1.
It is held by a bracket 6 and is connected to a supported body such as a piping system (not shown) via a connecting member 8 whose one end is pivotally supported by a bracket 6.

The piston bodies 9 and 10 are provided to protrude from opposite sides of the longitudinal side walls 1a and 1b of the oil case 1, and
Each inner side is slidably inserted into both sides of the cylinder 4. These piston bodies 9 and 10 create two oil chambers 1 in the cylinder 4 on both sides of the partition wall 5.
1 and 12 are formed. Each piston body 9, 10 is provided with oil passages 13, 14 which communicate the oil chambers 11, 12 with the outside.
5 and 16 are attached. Check valve 15, 16
When the hydraulic oil 0 that is about to flow out from each oil chamber 11, 12 through the oil passages 13, 14 has a speed higher than a predetermined value, it is pushed by the pressure and flows into the oil passages 13, 14.
14.

A piston ring 17 is fitted into the sliding contact portion between the outer periphery of the piston bodies 9 and 10 and the inner periphery of the cylinder 4. This piston ring has an abutment 18 as shown in FIGS. 4 and 5. This abutment 18 is designed to form a narrow ventilation space between the abutment 18 and the inner periphery of the cylinder 4 when installed.

A sliding cover 19 is fitted into the bracket 6 and is slidable on the cover 3.

Next, the effect will be explained. When the cylinder 4 moves horizontally in conjunction with a supported body (not shown), one of the oil chambers 11 and 12 expands while the other contracts. The oil in the reduced oil chamber tries to flow out to the case 1 through the oil passages 13 and 14, but the oil in the cylinder 4
If the movement is rapid, the check valves 15 and 16 are pushed by hydraulic pressure to close the oil passages 13 and 14,
Prevent movement of cylinder 4. This becomes the vibration damping force of the supported body. Oil chambers 11 and 12 on the side that expands on the other hand
In this case, oil 0 in the case 1 is sucked through the oil passages 14 and 13. On the other hand, when the supported body is slowly displaced due to thermal expansion or the like, the cylinder 4 moves slowly. For this reason, the oil chambers 11 and 12
The oil inside is discharged from the oil passages 13, 14 without closing the check valves 13, 14. Therefore, slow displacement of the supported body is allowed without difficulty. The oil in the cylinder 4 generates a small amount of gas due to oxidation or exposure to radiation. This gas collects at the upper part of the cylinder 4, and as each oil chamber expands and contracts as the supported body moves, it is discharged to the outside through the ventilation gap between the piston ring 17 and the inner circumference of the cylinder 4. Ru. Therefore, the compressibility of the gas disappears, and the damping effect is not affected. In addition, when the air in the cylinder 4 is removed when installing the device, the cylinder 4 is forced to reciprocate and the check valve 1 is removed.
5 and 16 to forcefully feed oil into each oil chamber 11 and 12, and air can also be removed from the ventilation gap. Therefore, no special air vent hole with plug is required. Furthermore, each oil chamber 11, 12 expands and contracts due to the vibration of the supported body, and the check valve 1
5 and 16 repeat opening and closing, but when the vibration subsides and the supported body comes to rest in the position where one of the oil chambers 11 and 12 is contracted, the check valve on the side of the contracted oil chamber is closed. The circuit remains closed. However, in this vibration isolator, the oil in each oil chamber 11, 12 gradually flows through the ventilation gap, so the check valve returns to its original position after a while. Therefore, no special consideration is required for the check valves 15 and 16 to prevent this.

It is assumed that the cylinder 4 is installed with a slight inclination. Taking this into consideration, the piston ring 17 can also be fitted around the outer periphery of the partition wall 5. In this case, the gas rises up the slope, passes through the ventilation gap between the partition wall 5 and the inner circumference of the cylinder 4, enters the oil chamber at the top of the slope, and the piston body 9 fitted therein,
The gas is discharged to the outside through the ventilation gap between the cylinder 10 and the cylinder 4.

As explained above, the present invention provides support S
Two piston bodies 9 and 10, which are fixed to and protrude oppositely into the oil in the oil case 1, are inserted into both sides of the cylinder 4, which is connected to a supported body and partitioned at the center. 9 and 10 have cylinder 4
In a hydraulic vibration isolator which is provided with a communication hole 14 that communicates with the outside and in which check valves 15 and 16 are interposed,
A piston ring 17 was fitted into the sliding contact portion of the piston bodies 9 and 10 with the cylinder 4 with its abutment 18 facing upward, and a narrow gap was formed between the abutment 18 and the inner circumference of the cylinder 4. Due to the structure, gas generated in the hydraulic oil and internal air during installation are prevented from being vented.
It can be discharged naturally through the check valves 15 and 16.
It is possible to provide a hydraulic vibration isolator with a simple and inexpensive structure that can reliably restore the structure.

[Brief explanation of the drawing]

1 is a plan view, FIG. 2 is a longitudinal front view, FIG. 3 is a sectional view of FIG. 2, FIG. 4 is an enlarged plan view of the piston ring, and FIG. 5 is an enlarged front view of the piston ring. DESCRIPTION OF SYMBOLS 1... Oil case, 4... Cylinder, 5... Partition wall, 9, 10... Piston body, 13, 14... Communication hole, 15, 16... Check valve, 17... Piston ring, 18... ...Application, 0...Hydraulic oil.

Claims (1)

[Scope of utility model registration request] Two piston bodies protruding oppositely into oil in an oil case fixed to a support are inserted into both sides of a cylinder connected to a supported body and partitioned at the center, and the piston bodies In this hydraulic vibration isolator, a communication hole is provided for communicating between the cylinder and the outside, and a check valve is interposed in the communication hole, in which a piston ring is placed in sliding contact with the cylinder of the piston body, with its abutment facing upward. A hydraulic vibration isolator characterized in that it is fitted in toward the direction of the cylinder to form a narrow gap between the abutment and the inner circumference of the cylinder.