JPS6234986B2 - - Google Patents

Description

Detailed Description of the Invention This invention prevents high-pressure gas from leaking around moving members such as rods and shafts that reciprocate or rotate through a partition wall between a high-pressure gas space and an atmospheric side space. The present invention relates to a high-pressure gas seal device for preventing.

For example, in engines, compressors, etc.
Moving members such as pistons, rods, or shafts make reciprocating or rotating motion between the working gas space and the atmosphere side space in the cylinder, and such movement is necessary to prevent the working gas from leaking. It is necessary to seal the gap between the member and the cylinder.
However, the gas space in the working gas space is extremely high and the pressure fluctuates, which is a complicated condition, and the reality is that it is not always possible to completely seal the gas.

Conventionally, such gas seals use a seal ring made of metal, rubber, or plastic material to tighten the outer circumferential surface of a moving member such as a rod. If the applied force is increased, the frictional resistance increases and the output loss increases, and there are problems in that moving members such as rods become more abrasive and the life of the seal itself is shortened.

In order to improve such problems, it has been proposed in the past to convert the pressure of high-pressure gas into hydraulic pressure and to seal the high-pressure gas with an oil seal that is relatively easy to seal. In other words, the compressibility of oil is extremely low compared to gas, while the viscosity is extremely high compared to gas, so the conditions for oil seals are more relaxed than for gas seals, and therefore the pressure Once converted to hydraulic pressure, high-pressure gas can be sealed relatively easily with an oil seal that is lenient to the conditions. However, even in this case, it is difficult to achieve a complete seal when the pressure of the high-pressure gas fluctuates rapidly or when vibrations are large, and if the gas and oil come into direct contact, the oil may ripple due to vibrations, etc. There is a problem that oil gets mixed into the gas, or conversely, gas gets caught up in the oil and leaks. Measures have been taken to counter this problem, such as placing a floating lid on the oil surface to prevent the oil from rippling, but these efforts have not always yielded satisfactory results.

This invention has been made in view of the above circumstances, and includes a slider mechanism that is slidable relative to a moving member such as a rod as a gas pressure-to-hydraulic converter inside the seal device, and thereby In addition to perfecting the gas seal by always balancing the hydraulic pressure with the gas pressure, it also ensures a perfect seal for high-pressure gas by preventing the gas and seal oil from mixing against vibrations and impulses. The purpose is to provide a high pressure gas seal.

Corresponding to this purpose, the high-pressure gas seal of the present invention is a sealing device around a moving member that penetrates a partition wall that partitions a high-pressure gas space and an atmosphere-side space, the sealing device being an intermediate between the high-pressure gas space and the atmosphere-side space. a first oil chamber that accommodates seal oil formed in the first oil chamber, and a second oil chamber that stores seal oil leaked from the first oil chamber;
an oil seal means provided between both oil chambers and between the second oil chamber and the atmosphere side space; a pressure regulating valve that limits an increase in the oil pressure in the first oil chamber;
a slider fitted around the moving member so as to be able to slide within a certain range between the oil chamber and the high pressure gas space; a first gas sealing means provided in a gap between the slider and the moving member; , a second gas sealing means provided in a gap between a sealing frame disposed outside the slider and the slider, and a second gas sealing means provided inside the slider for storing leaked gas that has passed through the first and second gas sealing means. A leakage gas reservoir is formed, an oil seal means for preventing seal oil from the first oil chamber from entering the leakage gas reservoir, and an expandable diaphragm placed between the seal frame and the slider. The present invention is characterized in that the slider is reciprocated within a certain range in accordance with the pressure space of the high-pressure gas space, so that the gas pressure and the oil pressure are constantly balanced.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In FIG. 1, 1 is a high-pressure gas space, 2 is an atmosphere side space, and 3 is a partition wall that partitions both spaces 1 and 2. As the moving member penetrating the partition wall 3, a reciprocating rod 4 is exemplified here, and the high pressure sealing device 5 of the present invention is installed around the rod 4. That is, in the through hole 6 formed in the partition wall 3, there is a seal frame 7 surrounding the rod 4,
8 and 9 are fixed to the partition wall 3 with an appropriate distance maintained by spacers 10 and 11 between them, and the space between the seal frames 7 and 8 becomes the first oil chamber 12, and the space between the seal frames 8 and 8 becomes the first oil chamber 12. 9 serves as a second oil chamber 13. A slider 14, which will be described later, is installed inside the seal frame 7 as a member that rubs against the circumferential surface of the rod 4. An oil scraper 15 and a pumping ring 16 are installed inside the seal frame 8 as oil sealing means. An oil scraper 17 is provided inside each as an oil seal means.

The slider 14 has one end 18 facing the high pressure gas space 1 and the other end 19 facing the first oil chamber 12, and has seal rings 20, 21 on the high pressure gas space 1 side and seal rings 20 and 21 between them on the inner surface that rubs against the rod 4. The first gas sealing means S1 is provided with a dump chamber 22 provided in the first oil chamber 12, and an oil scraper 23 is further provided as an oil sealing means on the first oil chamber 12 side.

Furthermore, a leak gas storage chamber 24 is provided inside the slider 14 to store leak gas that has passed through the first gas sealing means S1.

A second gas seal means S2 consisting of seal rings 25 and 26 and a dump chamber 27 between them is also provided in the gap between the seal frame 7 and the slider 14, and this second gas seal In order to prevent the leaked gas that has passed through the means S2 from entering the first oil chamber 12, an expandable diaphragm (bellows) 28 is connected between the seal frame 7 and the slider 14. The leaking gas that has passed through the second gas sealing means S2 enters the leaking gas reservoir chamber 24 through the through hole 29. The first oil chamber 12 is filled with seal oil 30 supplied from an oil tank (not shown), and this seal oil 30 receives pressure from the slider 14 which is pressed by high pressure gas. A pressure regulating valve 31 is provided in the seal frame 8,
It is designed to adjust the pressure of the seal oil in the first oil chamber 12 when it becomes extremely high. This pressure regulating valve 31 has a hole 32 communicating with the first oil chamber 12.
The ball 33 blocking the diaphragm spring 34
It is pressed by a plunger 35 via. This plunger 35 is always pushed toward the first oil chamber by a spring 36. The rear end of the spring 36 is received by a seal nut 37. The pressure chamber 38 in which the spring 36 is disposed is connected to the high pressure gas space 1 by a narrow communication passage 39.
Gas pressure is introduced from

That is, a capillary screw 41 having a thin hole is attached to an inner frame 40 arranged inside the seal frame 7, and a dump chamber 42 provided between the seal frame 7 and the inner frame 40 is connected to the capillary screw 41.
The communication path 39 is connected to the seal frame 7 and the spacer 10.
and communicates with the pressure chamber 38 through the seal frame 8. Therefore, the plunger 35 of the pressure regulating valve
Since the ball 33 is pressed by both the elastic force of the spring 36 and the gas pressure in the pressure chamber 38, seal oil will not flow in from the hole 32 unless the oil pressure in the first oil chamber 12 becomes extremely high. There's nothing to do. Further, the gas introduced into the pressure chamber 38 is sealed by a gas seal ring 43 and a seal nut 37 provided around the plunger 35 so as not to leak to the outside. The aforementioned inner frame 40 is provided with a stopper 44 for limiting the sliding range of the slider 14. The second oil chamber 13 is for storing the seal oil leaked from the first oil chamber 12, but when the oil pressure of the seal oil accumulated inside the second oil chamber 13 exceeds a predetermined value, the pressure regulating valve 45 is activated. It functions to allow seal oil to escape to the atmosphere. The pressure regulating valve 45 has a ball 47 that closes a hole 46 made in the seal frame 9, a spring 48 that pushes the ball, and a nut 49 that receives the rear end of the spring 48. A small hole 50 is drilled leading to the. Note that seal rings 51, 52, and 53 are also attached to the outer peripheries of the seal frames 7, 8, and 9, respectively. In this embodiment, oil scrapers 15, 17, 2 are used as oil seal means.
3 not only serves as a seal, but also serves to scrape off seal oil adhering to the outer surface of the rod 4. The part in contact with the rod 4 is the peak line of the mountain shape as shown in the figure, and since the inclination angles on both the left and right sides of this peak line are larger on one side and smaller on the other, it has a somewhat pumping effect. For example, regarding the oil scraper 15, the first oil chamber 1
It has a property that it is difficult for oil to leak from the second oil chamber 13 side, but it is easy for oil to leak from the second oil chamber 13 side. This also applies to the pumping ring 16. The pumping ring 16 is made of metal or plastic material, and its inner surface has a gentle chevron shape, with a first
Since the slope toward the oil chamber side is steep and the slope toward the second oil chamber side is gentle, it is difficult for oil from the first oil chamber side to pass through, and oil from the second oil chamber side is easy to pass through. There is. Therefore, when the rod 4 reciprocates, the second
It has a pump function that allows the oil in the oil chamber to flow back little by little to the first oil chamber.

The high-pressure sealing device of the present invention converts the pressure of high-pressure gas into hydraulic pressure and seals the high-pressure gas with an easy-to-seal oil seal, and employs a slider 14 as a means for converting the gas pressure into hydraulic pressure. An important feature is that the slider 14 is automatically slid within a certain range as the gas pressure fluctuates, thereby constantly balancing the gas pressure and oil pressure.

That is, the slider 14 can freely slide within the range between the seal frame 8 and the stopper 44, and since its one end 18 faces the high pressure gas space 1, it receives the pressure of the high pressure gas and moves into the first oil chamber 1.
Since the seal oil 30 in 2 is compressed, the seal oil 3
0 pressure increases, and as a result, it comes to rest at a position where gas pressure and oil pressure are balanced. When the gas pressure increases, the slider 14 is pushed toward the first oil chamber 12 and comes to rest again at a position where the oil pressure is balanced. Conversely, if the gas pressure becomes low, it will be pushed by the oil pressure and will slide to a position where the gas pressure and oil pressure are in balance and come to rest. In this way, the slider 14 naturally slides as the gas pressure fluctuates and balances the oil pressure, so the seal oil in the first oil chamber can almost completely prevent gas leakage, and the rest is done in the first oil chamber. All you need to do is prevent the seal oil from leaking inside the oil chamber. Of course, the high pressure gas tends to leak from the gap 54 between the rod 4 and the slider 14 and the gap 55 between the slider 14 and the seal frame 7, but these gaps have first and second
Since gas sealing means S1 and S2 are provided, gas leakage is prevented. For example, in the first gas sealing means S1, gas that attempts to leak through the gap 54 is first blocked by the seal ring 20, but the gas that has passed through there also enters the dump chamber 22 and is under pressure. The pressure is reduced and stabilized. Therefore, gas leakage is almost completely prevented by the next seal ring 21. Even if it passes through the seal ring 21, the pressure is further reduced and made constant in the leakage gas reservoir chamber 24, eliminating pressure fluctuations. This kind of action is caused by the sealing 2 applied to the gap 55.
The same applies to the second gas sealing means S2, which is comprised of the dump chamber 27, and the gas that has passed through the first gas sealing means S2 ends up entering the leakage gas storage chamber 24. The pressure of the leaked gas that has entered the leakage gas storage chamber 24 will never be higher than the gas pressure in the high-pressure gas space 1, and even if it becomes the same, it will be in equilibrium with the oil pressure in the first oil chamber 12. , gas will not leak from the leakage gas reservoir chamber 24 to the first oil chamber.

Also, the seal oil in the first oil chamber is removed from the slider 14.
Even if the oil tries to enter the leakage gas reservoir chamber 24 through the gap between the oil scraper 2 and the rod 4, there is no oil scraper 2 here.
3 prevents infiltration.

On the other hand, leakage from the first oil chamber 12 to the second oil chamber 13 occurs through the oil scraper 15 and the pumping ring 1.
The seal oil flows backward from the second oil chamber 13 by the pump action of 6. The pressure regulating valve 31 has a pressure chamber 38
Since the hole 32 is closed by the gas pressure inside and the elastic force of the spring 36, seal oil does not leak from the hole 32 at all times, but the oil pressure in the first oil chamber is higher than the gas pressure. When the temperature rises abnormally, the ball 33 is used to drain the seal oil from the bypass 56.
The oil is released to the oil chamber 13 and the oil pressure in the first oil chamber 12 is adjusted. Therefore, the slider 14 is the stopper 44.
This can prevent the original function from being lost due to collision.

Furthermore, the seal oil stored in the second oil chamber 13 is prevented from leaking into the atmosphere side space by the oil scraper 17, but if the oil pressure in the second oil chamber 13 becomes too high, , actuate the pressure regulating valve 45 with the pressure, push the ball 47,
The seal oil in the second oil chamber can be released to the outside through the hole 46 and the small hole 50, and the pressure inside the second oil chamber can be adjusted.

In this way, high-pressure gas sealing can be ensured. In particular, in the case of the present invention, the slider 14 is automatically moved in response to fluctuations in the high-pressure gas, thereby constantly balancing the oil pressure of the seal oil. This has the effect of efficiently and reliably sealing high-pressure gas leaks even when the gas pressure fluctuates rapidly. Furthermore, since the expandable and retractable diaphragm 28 is used to prevent direct contact between the high pressure gas and the seal oil, there is no risk of the gas and oil mixing even if vibrations or impulses are severe, ensuring complete safety.
In addition, although an oil scraper, a pumping ring, etc. are illustrated as oil seal means in the embodiment, various other seal means may be used, and the pressure introduced into the pressure chamber 38 of the pressure regulating valve 31 is as follows: Hydraulic pressure may be used instead of gas pressure.

Further, in the embodiment, a rod that reciprocates as a moving member is shown, but the sealing device of the present invention can also be applied to other shafts that rotate.

[Brief explanation of the drawing]

The drawing is an explanatory cross-sectional view showing one embodiment of a high-pressure gas seal device according to the present invention. 1...High pressure gas space, 2...Atmospheric side space, 3...
...Partition wall, 4... Rod (moving member), 5... Seal device, 7, 8, 9... Seal frame, 12... First
Oil chamber, 13...Second oil chamber, 14...Slider,
S1...First gas sealing means, S2...Second gas sealing means, 24...Leak gas storage chamber, 27...
Dump chamber, 28... diaphragm, 31... pressure regulating valve,
45...Pressure regulating valve.

Claims (1)

[Claims] 1. A sealing device around a moving member that penetrates a partition wall that partitions a high-pressure gas space and an atmosphere side space,
A first oil chamber that accommodates seal oil is formed between the high-pressure gas space and the atmosphere side space, and a second oil chamber that stores seal oil leaked from the first oil chamber, and between these two oil chambers. and an oil seal means provided between the second oil chamber and the atmosphere side space, a pressure regulating valve that limits an increase in oil pressure in the first oil chamber, and between the first oil chamber and the high pressure gas space. a slider fitted around the moving member so as to be able to slide within a certain range; a first gas sealing means provided in a gap between the slider and the moving member; and a first gas sealing means disposed outside the slider. a second gas sealing means provided in a gap between the seal frame and the slider; a leakage gas storage chamber formed inside the slider for storing leakage gas that has passed through the first and second gas sealing means; It is equipped with an oil seal means for preventing the seal oil from the first oil chamber from entering the leakage gas storage chamber, and a retractable diaphragm placed between the seal frame and the slider, and a high-pressure gas space. A high-pressure gas seal device, characterized in that the slider is reciprocated within a certain range in response to pressure fluctuations, thereby constantly balancing gas pressure and oil pressure. 2. The high-pressure gas seal device according to claim 1, characterized in that the resilient force of a spring and the gas pressure introduced from the high-pressure gas space are used together as the force for always closing the pressure regulating valve. 3. The high-pressure gas seal device according to claim 1 or 2, wherein an oil scraper is used as the oil seal means. 4. As one of the oil seal means provided between the first oil chamber and the second oil chamber, a pumping ring having a function of causing seal oil to flow back from the second oil chamber to the first oil chamber is used. A high-pressure gas seal device according to claim 1, 2, or 3. 5. The high-pressure sealing device according to claim 1, 2, 3, or 4, further comprising a pressure regulating valve that limits an increase in oil pressure in the second oil chamber. 6. Claims 1, 2, and 3, wherein each of the first and second gas seal means has a plurality of gas seal rings and a dump chamber interposed between them. Section 4 or Section 5
High-pressure sealing device as described in section.